Vitamin D: Wikis

  
  
  

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.
Calcium regulation in the human body.
^ Vitamin D is an essential vitamin the body needs to regulate the amount of calcium and phosphorus in the body.
  • ACS :: Vitamin D 28 January 2010 2:02 UTC www.cancer.org [Source type: Academic]

^ Vitamin D supplement helps the body to regulate the transport of calcium from the digestive system through the bloodstream to bone.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Consequently, there is no great drain on maternal vitamin D reserves either to regulate calcium homeostasis or to supply the need of human milk.
  • Chapter 8. Vitamin D 28 January 2010 2:02 UTC www.fao.org [Source type: Academic]

[1] The role of vitamin D is shown in orange.
.Vitamin D is a group of fat-soluble prohormones, the two major forms of which are vitamin D2 (or ergocalciferol) and vitamin D3 (or cholecalciferol).^ A. Supplemental vitamin D comes in two forms: D2 (ergocalciferol) or D3 (cholecalciferol).

^ Vitamin D refers to a group of fat-soluble prohormones , the two major forms of which are vitamin D 2 (or ergocalciferol ) and vitamin D 3 (or cholecalciferol ).

^ Vitamin D is the family of prohormones which work as fat-soluble.
  • Vitamin D -- Why You Are Probably NOT Getting Enough 28 January 2010 2:02 UTC www.ultrawellness.com [Source type: General]

[2] .Vitamin D obtained from sun exposure, food, and supplements is biologically inert and must undergo two hydroxylation reactions to be activated in the body.^ Vitamin D from Sun or supplement pill?
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Vitamin D obtained from sun exposure, food, and supplements, is biologically inert and must undergo two hydroxylation reactions to be activated in the body.
  • Vitamin D 2 February 2010 18:56 UTC www.squidoo.com [Source type: General]

^ The body can make vitamin D after exposure to UV rays or it can be obtained through some foods or supplements.
  • ACS :: Vitamin D 28 January 2010 2:02 UTC www.cancer.org [Source type: Academic]

.Calcitriol (1,25-Dihydroxycholecalciferol) is the active form of vitamin D found in the body.^ Prostate cancer: In the body, vitamin D is processed to its active form, 1,25-dihydroxy vitamin D, also known as calcitriol.
  • Sloan-Kettering - Vitamin D 28 January 2010 2:02 UTC www.mskcc.org [Source type: Academic]

^ Calcitriol is 1, 25 dihydroxycholecalciferol.
  • Calciferol online 11 September 2009 3:03 UTC buy.net-fast.org [Source type: Academic]

^ Retinol is the most active form of vitamin A. .
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

.The term vitamin D also refers to these metabolites and other analogues of these substances.^ The term vitamin D also refers to these metabolites and other analogues of these substances.
  • Vitamin D 2 February 2010 18:56 UTC www.squidoo.com [Source type: General]

^ The term vitamin D also refers to metabolites and other analogues of these substances.

^ The term "vitamin D" refers to several different forms of this vitamin.
  • Vitamin D: MedlinePlus Supplements 28 January 2010 2:02 UTC www.nlm.nih.gov [Source type: Academic]
  • Vitamin D - Drugs & Treatments - Revolution Health 28 January 2010 2:02 UTC www.revolutionhealth.com [Source type: Academic]
  • Susan G. Komen for the Cure | Understanding Breast Cancer | Complementary Therapies | Vitamin D 2 February 2010 18:56 UTC ww5.komen.org [Source type: Academic]

.Calcitriol plays an important role in the maintenance of several organ systems.^ Calcitriol plays an important role in the maintenance of several organ systems.
  • Vitamin D 2 February 2010 18:56 UTC www.squidoo.com [Source type: General]

^ Vitamin D plays an important role in the maintenance of several organ systems.

^ Role of vitamin D prohormone Vitamin D has an important role in the function of organ systems.
  • Vitamin-D supplement 400 iu tablets, fat solube prohormone 2 February 2010 18:56 UTC www.physicianformulas.com [Source type: Academic]

[3] .However, its major role is to increase the flow of calcium into the bloodstream, by promoting absorption of calcium and phosphorus from food in the intestines, and reabsorption of calcium in the kidneys; enabling normal mineralization of bone and preventing hypocalcemic tetany.^ The major function of vitamin D is to increase the efficiency of calcium absorption from the small intestine.
  • Vitamin D Deficiency and Related Disorders: eMedicine Endocrinology 28 January 2010 2:02 UTC emedicine.medscape.com [Source type: Academic]

^ Vitamin D intake increases both calcium and phosphorus absorption.

^ This is essential for the normal mineralization of bone and preventing hypocalcemic tetany.
  • What Is Vitamin D? What Are The Benefits Of Vitamin D? 2 February 2010 18:56 UTC www.medicalnewstoday.com [Source type: Academic]

.It is also necessary for bone growth and bone remodeling by osteoblasts and osteoclasts.^ It is also necessary for bone growth and bone remodeling by osteoblasts and osteoclasts.
  • Vitamin D 2 February 2010 18:56 UTC www.squidoo.com [Source type: General]

^ It is also needed for bone growth and bone remodeling by osteoblasts and osteoclasts.
  • Ultimate Vitamin Guide: Vitamin D | Womens Health Base 28 January 2010 2:02 UTC www.womenshealthbase.com [Source type: Academic]

^ It is also required for proper bone growth and bone remodeling by osteoblasts and osteoclasts.
  • Vitamin D 2 February 2010 18:56 UTC www.squidoo.com [Source type: General]

[4][5]
.A lack of moderate sun exposure is the major cause of vitamin D deficiency.^ Vitamin D deficiency in childhood causes rickets.
  • Dining@Large: The vitamin D dilemmas - Elizabeth Large blogs about memorable meals, dining trends, comings and goings on the restaurant scene and more. - baltimoresun.com 28 January 2010 2:02 UTC weblogs.baltimoresun.com [Source type: General]

^ Vitamin D deficiency does not cause rickets.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

^ Vitamin C deficiency causes scurvy.
  • Dining@Large: The vitamin D dilemmas - Elizabeth Large blogs about memorable meals, dining trends, comings and goings on the restaurant scene and more. - baltimoresun.com 28 January 2010 2:02 UTC weblogs.baltimoresun.com [Source type: General]

.Deficiency is defined as a serum 25-hydroxyvitamin D level of less than 20 ng/mL. Recommended doses of vitamin D are now 800 to 1000 IU daily.^ "Serum 25-hydroxyvitamin D levels and risk of multiple sclerosis".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Vitamin D deficiency was defined as serum 25(OH)D 20 ng/ml and insufficiency as 21–29 ng/ml respectively.
  • Obesity - Vitamin D Status and Response to Vitamin D3 in Obese vs. Non-obese African American Children 28 January 2010 2:02 UTC www.nature.com [Source type: Academic]

^ Vitamin D deficiency is now considered to be a pandemic.
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

[6] .Without sufficient vitamin D, bones can become thin, brittle, or misshapen.^ Without sufficient vitamin D, bones can become thin, brittle, or misshapen.
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]
  • Vitamin D - Medpedia 28 January 2010 2:02 UTC wiki.medpedia.com [Source type: Academic]
  • Ultimate Vitamin Guide: Vitamin D | Womens Health Base 28 January 2010 2:02 UTC www.womenshealthbase.com [Source type: Academic]
  • Vitamin D 28 January 2010 2:02 UTC www.hoptechno.com [Source type: Academic]

^ Without vitamin D, bones can become thin, brittle, or misshapen.
  • Vitamin D -- To be free from influenza and many diseases 28 January 2010 2:02 UTC www.allanstime.com [Source type: Academic]

^ Without vitamin D, bones can become thin, brittle, soft, or misshapen.

.Deficiency can arise from inadequate intake coupled with inadequate sunlight exposure; disorders that limit its absorption; conditions that impair conversion of vitamin D into active metabolites, such as liver or kidney disorders; or, rarely, by a number of hereditary disorders.^ The liver and kidney help convert vitamin D to its active hormone form [ 3 ].
  • Vitamin D -- To be free from influenza and many diseases 28 January 2010 2:02 UTC www.allanstime.com [Source type: Academic]

^ Deficiency can arise from inadequate intake coupled with inadequate sunlight exposure; disorders that limit its absorption; conditions that impair conversion of vitamin D into active metabolites, such as liver or kidney disorders; or, rarely, by a number of hereditary disorders.
  • Vitamin D 2 February 2010 18:56 UTC www.squidoo.com [Source type: General]

^ The liver and kidney help convert vitamin D to its active hormone form 3 .

.Vitamin D deficiency results in impaired bone mineralization and leads to bone softening diseases, rickets in children and osteomalacia in adults, and possibly contributes to osteoporosis.^ Associated with vitamin D deficiency and rickets in infants and young children.
  • Ultimate Vitamin Guide: Vitamin D | Womens Health Base 28 January 2010 2:02 UTC www.womenshealthbase.com [Source type: Academic]
  • Vitamin D Analogues 28 January 2010 2:02 UTC www.globalrph.com [Source type: Academic]

^ Osteomalacia is a form of adult ricket.
  • Vitamin D Information - Benefits, Deficiency, Sources, Dosage 28 January 2010 2:02 UTC www.healthvitaminsguide.com [Source type: FILTERED WITH BAYES]

^ Vitamin D sufficiency prevents rickets in children and osteomalacia in adults.
  • Ultimate Vitamin Guide: Vitamin D | Womens Health Base 28 January 2010 2:02 UTC www.womenshealthbase.com [Source type: Academic]

[3] .Compared to normal intakes humans have an enormous capacity for storing vitamin D and overdose is extremely rare.^ Vitamin D stored in the human body as calcidiol (25-hydroxy-vitamin D) has a large volume of distribution and a long half-life (about 20 to 29 days).

^ Cutaneously synthesized Vitamin D is stored in fat tissue and obese individuals have greater than 50% less bioavailability of Vitamin D compared to non-obese individuals.
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Vitamin D excess, however, is rarely seen in the general human population.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

.Vitamin D plays a number of other roles in human health including inhibition of calcitonin release from the thyroid gland.^ Vitamin D has an important role in cardiovascular health.

^ Vitamin D has other roles in human health, including modulation of neuromuscular and immune function and reduction of inflammation.
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]
  • Ultimate Vitamin Guide: Vitamin D | Womens Health Base 28 January 2010 2:02 UTC www.womenshealthbase.com [Source type: Academic]
  • Vitamin D 28 January 2010 2:02 UTC www.hoptechno.com [Source type: Academic]

^ D plays an important role in your health.
  • Vitamin D | LIVESTRONG.COM 28 January 2010 2:02 UTC www.livestrong.com [Source type: FILTERED WITH BAYES]

.Calcitonin acts directly on osteoclasts, resulting in inhibition of bone resorption and cartilage degradation.^ Calcitonin acts directly on osteoclasts, resulting in inhibition of bone resorption and cartilage degradation.
  • Vitamin D 2 February 2010 18:56 UTC www.squidoo.com [Source type: General]

^ Without sufficient vitamin D, inadequate calcium is absorbed and the resulting elevated parathyroid (PTH) secretion causes increased bone resorption.
  • Vitamin D: MedlinePlus Supplements 28 January 2010 2:02 UTC www.nlm.nih.gov [Source type: Academic]
  • Susan G. Komen for the Cure | Understanding Breast Cancer | Complementary Therapies | Vitamin D 2 February 2010 18:56 UTC ww5.komen.org [Source type: Academic]

^ The role of calcitonin in calcium homeostasis is to decrease elevated serum calcium levels by inhibiting bone resorption.

.Vitamin D can also inhibit parathyroid hormone secretion from the parathyroid gland, modulate neuromuscular and immune function and reduce inflammation.^ Vitamin D and paricalcitol have been shown to reduce parathyroid hormone levels by inhibiting PTH synthesis and secretion.
  • Vitamin D Analogues 28 January 2010 2:02 UTC www.globalrph.com [Source type: Academic]

^ Vitamin D has other roles in human health, including modulation of neuromuscular and immune function and reduction of inflammation.
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]
  • Vitamin D - Medpedia 28 January 2010 2:02 UTC wiki.medpedia.com [Source type: Academic]
  • Ultimate Vitamin Guide: Vitamin D | Womens Health Base 28 January 2010 2:02 UTC www.womenshealthbase.com [Source type: Academic]
  • Vitamin D 28 January 2010 2:02 UTC www.hoptechno.com [Source type: Academic]

^ Vitamin D can also inhibit parathyroid hormone secretion from the parathyroid gland, modulate neuromuscular and immune function and reduce inflammation.
  • Vitamin D 2 February 2010 18:56 UTC www.squidoo.com [Source type: General]

[7][8][9]

Contents

Forms

Name Chemical composition Structure
Vitamin D1 molecular compound of ergocalciferol with lumisterol, 1:1
Vitamin D2 ergocalciferol (made from ergosterol) Note double bond at top center.
Vitamin D3 cholecalciferol .(made from 7-dehydrocholesterol in the skin).^ Vitamin D, a seco-steroid, can either be made in the skin from a cholesterol-like precursor (7-dehydrocholesterol) by exposure to sunlight or can be provided pre-formed in the diet ( 1 ).
  • Chapter 8. Vitamin D 28 January 2010 2:02 UTC www.fao.org [Source type: Academic]

^ Vitamin D 3 is derived from animal sources and is made in the skin when 7-dehydrocholesterol reacts with UVB ultraviolet light at wavelengths between 270–290 nm.

^ Cholecalciferol (vitamin D 3 ) is made from 7-dehydrocholesterol in the skin of animals and humans.
  • eMJA: Vitamin D intake and vitamin D status of Australians 11 September 2009 3:03 UTC www.mja.com.au [Source type: Academic]

Cholecalciferol.svg
Vitamin D4 22-dihydroergocalciferol 22-Dihydroergocalciferol.png
Vitamin D5 sitocalciferol (made from 7-dehydrositosterol) VitaminD5 structure.png
.Several forms (vitamers) of vitamin D have been discovered (see table).^ Several forms of vitamin D have been described.

^ The term "vitamin D" refers to several different forms of this vitamin.
  • Vitamin D: MedlinePlus Supplements 28 January 2010 2:02 UTC www.nlm.nih.gov [Source type: Academic]
  • Vitamin D - Drugs & Treatments - Revolution Health 28 January 2010 2:02 UTC www.revolutionhealth.com [Source type: Academic]
  • Vitamin D | LIVESTRONG.COM 28 January 2010 2:02 UTC www.livestrong.com [Source type: FILTERED WITH BAYES]
  • Susan G. Komen for the Cure | Understanding Breast Cancer | Complementary Therapies | Vitamin D 2 February 2010 18:56 UTC ww5.komen.org [Source type: Academic]

^ Vitamin D --also known as calciferol --has several forms or metabolites.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

.The two major forms are vitamin D2 or ergocalciferol, and vitamin D3 or cholecalciferol.^ Vitamin D is a group of fat-soluble prohormones , the two major forms of which are vitamin D 2 (or ergocalciferol ) and vitamin D 3 (or cholecalciferol ).

^ The two major forms are Vitamin D2 and Vitamin D3.
  • Vitamin D: What Is Vitamin D, Why We Need It, How To Get It 28 January 2010 2:02 UTC www.savvyvegetarian.com [Source type: Academic]

^ The two forms of vitamin D used in dietary supplements are ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3).
  • WHFoods: vitamin D 28 January 2010 2:02 UTC www.whfoods.com [Source type: Academic]
  • WHFoods: vitamin D 2 February 2010 18:56 UTC www.whfoods.com [Source type: Academic]

.These are known collectively as calciferol.^ They are known collectively as calciferol .
  • What Is Vitamin D? What Are The Benefits Of Vitamin D? 2 February 2010 18:56 UTC www.medicalnewstoday.com [Source type: Academic]

[10] .Vitamin D2 was chemically characterized in 1932. In 1936 the chemical structure of vitamin D3 was established and resulted from the ultraviolet irradiation of 7-dehydrocholesterol.^ There are two forms of vitamin D. Vitamin D3 is made in the body from a chemical reaction to the ultraviolet radiation in sunlight.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Vitamin D 2 is manufactured through the ultraviolet irradiation of ergosterol from yeast, and vitamin D 3 through the ultraviolet irradiation of 7-dehydrocholesterol from lanolin.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ A precursor to vitamin D exists naturally in the skin, and exposure to the sun's ultraviolet (UV) rays touches off a chemical process that creates the usable form of the vitamin.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

[11]
.Chemically, the various forms of vitamin D are secosteroids; i.e., steroids in which one of the bonds in the steroid rings is broken.^ Vitamin D 4 : dihydrotachysterol Vitamin D 5 : sitocalciferol (made from 7-dehydrositosterol ) Chemically, the various forms of vitamin D are secosteroids ; i.e.

^ Vitamin D is one of the fat-soluble vitamins that comes in two major forms; these are vitamin D2 (or ergocalciferol) and vitamin D3 (or cholecalciferol).
  • Vitamin D Supplements at the Lowest Prices! 2 February 2010 18:56 UTC www.a1supplements.com [Source type: General]

^ UVB acts on a chemical in the skin, one of the by-products of cholesterol metabolism, to form other chemicals which then become Vitamin D. Vitamin D is intimately involved in the normal growth and development of bone, and in the absorption of calcium from food and its deposition in bone.

[12] .The structural difference between vitamin D2 and vitamin D3 is in their side chains.^ Q. What’s the difference between vitamin D2 and D3?

^ The structural difference between vitamin D 2 and vitamin D 3 is in their side chains .

^ [CrossRef] [Web of Science] [Medline] McKenna MJ. Differences in vitamin D status between countries in young adults and the elderly.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

The side chain of D2 contains a double bond between carbons 22 and 23, and a methyl group on carbon 24.
.Vitamin D2 (made from ergosterol) is produced by invertebrates, fungus and plants in response to UV irradiation; it is not produced by vertebrates.^ Ergocalciferol (vitamin D 2 ) is produced by UV irradiation of the fungal steroid ergosterol.
  • eMJA: Vitamin D intake and vitamin D status of Australians 11 September 2009 3:03 UTC www.mja.com.au [Source type: Academic]

^ Vitamin D 2 is formed by the action of UV-B on the plant precursor ergosterol.

^ Ergocalciferol (vitamin D 2 ) is formed by uv irradiation of ergosterol.

.Little is known about the biologic function of vitamin D2 in nonvertebrate species.^ Many of the biological effects of 1,25(OH) 2 D are mediated through a nuclear transcription factor known as the vitamin D receptor (VDR) (4) .
  • Linus Pauling Institute at Oregon State University 28 January 2010 2:02 UTC lpi.oregonstate.edu [Source type: Academic]

^ The major biologic function of vitamin D is to maintain normal blood levels of calcium and phosphorus .
  • Vitamin D - Medpedia 28 January 2010 2:02 UTC wiki.medpedia.com [Source type: Academic]

^ Once formed, 1,25(OH)2D3 carries out the biologic functions of vitamin D3 on the intestine and bone.
  • Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride 28 January 2010 2:02 UTC www.nap.edu [Source type: Academic]

.Because ergosterol can more efficiently absorb the ultraviolet radiation that can damage DNA, RNA and protein it has been suggested that ergosterol serves as a sunscreening system that protects organisms from damaging high energy ultraviolet radiation.^ Evidence for a protective effect of ultraviolet radiation.
  • Vitamin D 28 January 2010 2:02 UTC healthlibrary.epnet.com [Source type: Academic]
  • Vitamin D | ThirdAge Articles 28 January 2010 2:02 UTC www.thirdage.com [Source type: Academic]
  • Disease, Condition, & Injury Fact Sheets | NYU Langone Medical Center 28 January 2010 2:02 UTC www.med.nyu.edu [Source type: Academic]

^ It has been speculated that people living at higher altitudes may be able to more efficiently produce vitamin D3 in their skin because there is less ozone to absorb the UVB photons.

^ Duthie MS, Kimber I, Norval M. The effects of ultraviolet radiation on the human immune system.
  • ACS :: Vitamin D 28 January 2010 2:02 UTC www.cancer.org [Source type: Academic]

[13]
.Vitamin D3 is made in the skin when 7-dehydrocholesterol reacts with UVB ultraviolet light at wavelengths between 270–300 nm, with peak synthesis occurring between 295-297 nm.^ Vitamin D 3 is derived from animal sources and is made in the skin when 7-dehydrocholesterol reacts with UVB ultraviolet light at wavelengths between 270–290 nm.

^ The skin makes vitamin D from ultraviolet light.
  • vitamin d « FOX News Health Blog « FOXNews.com 28 January 2010 2:02 UTC health.blogs.foxnews.com [Source type: FILTERED WITH BAYES]

^ Cholecalciferol (vitamin D 3 ) is made from 7-dehydrocholesterol in the skin of animals and humans.
  • eMJA: Vitamin D intake and vitamin D status of Australians 11 September 2009 3:03 UTC www.mja.com.au [Source type: Academic]

[14][15] .These wavelengths are present in sunlight when the UV index is greater than 3. At this solar elevation, which occurs daily within the tropics, daily during the spring and summer seasons in temperate regions, and almost never within the arctic circles, adequate amounts of vitamin D3 can be made in the skin after only ten to fifteen minutes of sun exposure every day of the week to almost the entire body, in noon-day sun without sunscreen.^ Fifteen facts you probably never knew about vitamin D and sunlight exposure.
  • D/UV Vitamin D Lamp - Vitamin D production with Ultraviolet Light - DUV Sunlamp. 28 January 2010 2:02 UTC www.summertan.com [Source type: FILTERED WITH BAYES]

^ It is only when the UV index is greater than 3 that these UVB wavelengths are present.
  • What Is Vitamin D? What Are The Benefits Of Vitamin D? 2 February 2010 18:56 UTC www.medicalnewstoday.com [Source type: Academic]

^ At this solar elevation, which occurs daily within the tropics , daily during the spring and summer seasons in temperate regions , and almost never within the arctic circles , adequate amounts of vitamin D 3 can be made in the skin only after ten to fifteen minutes of sun exposure at least two times per week to the face, arms, hands, or back without sunscreen.

.This is assuming that the person is living at the approximate right "latitude" for their skin colour.^ The groups at greatest risk of vitamin D deficiency in Australia are dark-skinned and veiled women (particularly in pregnancy), their infants, and older persons living in residential care.
  • eMJA: Vitamin D intake and vitamin D status of Australians 11 September 2009 3:03 UTC www.mja.com.au [Source type: Academic]

^ The latitude at which a person lives, determines how much exposure to sunlight the person requires to synthesize adequate levels of vitamin D. Pollution, clouds, and skin color also affect an individual's ability to produce vitamin D. The darker the skin, the less vitamin D will be produced (95% blocked).

^ Persons living at latitudes north of the 37th parallel cannot get their vitamin D naturally during the winter months because of the sun's angle.
  • Vitamin D 28 January 2010 2:02 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

.However, season, geographic latitude, time of day, cloud cover, skin cover, skin color, smog, and sunscreen affect UV ray absorption and vitamin D synthesis.^ Season, latitude, and ability of sunlight to promote synthesis of vitamin D3 in skin.

^ Season, geographic latitude , time of day, cloud cover, smog , and sunscreen affect UV ray exposure and vitamin D synthesis in the skin, and it is important for individuals with limited sun exposure to include good sources of vitamin D in their diet.

^ The balance of UVA/UVB changes with latitude, time of day, and season.
  • Vitamin D: What Is Vitamin D, Why We Need It, How To Get It 28 January 2010 2:02 UTC www.savvyvegetarian.com [Source type: Academic]

.For example, sunlight exposure from November through February in Boston is insufficient to produce significant vitamin D synthesis in the skin.^ It is also produced endogenously when ultraviolet rays from sunlight strike the skin and trigger vitamin D synthesis [1-3].
  • Vitamin D Analogues 28 January 2010 2:02 UTC www.globalrph.com [Source type: Academic]

^ It is also produced endogenously when ultraviolet rays from sunlight strike the skin and trigger vitamin D synthesis.
  • Ultimate Vitamin Guide: Vitamin D | Womens Health Base 28 January 2010 2:02 UTC www.womenshealthbase.com [Source type: Academic]

^ Vitamin D3 is produced in the skin during exposure to sunlight.

[16] .With longer exposure to UVB rays, an equilibrium is achieved in the skin, and excess vitamin D simply degrades as fast as it is generated.^ With longer exposure to UVB rays, an equilibrium is achieved in the skin, and the vitamin simply degrades as fast as it is generated.

^ Season, geographic latitude , time of day, cloud cover, smog , and sunscreen affect UV ray exposure and vitamin D synthesis in the skin, and it is important for individuals with limited sun exposure to include good sources of vitamin D in their diet.

^ Spring, fall and summer noontime sunshine exposure provides adequate Vitamin D. Stay out a short time if your skin is light, but stay out longer if your skin is dark.
  • Amazon.com: Carlson Vitamin D3 2000 Iu, 120 Softgels, Bottle: Health & Personal Care 28 January 2010 2:02 UTC www.amazon.com [Source type: General]

[17] .The skin type affects vitamin D levels, lower vitamin D serum levels were found in fair skinned types in Britain, within Caucasians.^ Vitamin D's main role is to maintain serum calcium and phosphorus levels within the normal range to sustain a wide variety of metabolic and physiological functions, including maintaining bone health and normal neuromuscular function.
  • eMJA: Vitamin D intake and vitamin D status of Australians 11 September 2009 3:03 UTC www.mja.com.au [Source type: Academic]

^ These findings suggest a potential vasculoprotective role of vitamin D" Inverse association between serum 25(OH) vitamin D levels and non-melanoma skin cancer in elderly men - Cancer Causes Control.

^ Another small study found an increased protective effect of high levels of vitamin D only in women.
  • | Reference Library | WholeHealthMD 28 January 2010 2:02 UTC www.wholehealthmd.com [Source type: Academic]

[18] .This finding is not consistent with the predominant hypothesis concerning the evolution of white skin, that it evolved to prevent vitamin D deficiency[19] There are other explainations for why Europeans have pale skin that are consistent with the lightest skin being found at high latitude (within Europe), such as resistance to frostbite[20][21] and sexual selection in human evolution.^ [Prevention of vitamin D deficiency in adolescents and pre-adolescents.

^ A diet high in oily fish prevents vitamin D deficiency.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ The skin lotion is preventing vitamin D from being absorbed,” Politi said.

.Both vitamin D2 and D3 are used for human nutritional supplementation, and pharmaceutical forms include calcitriol (1alpha, 25-dihydroxycholecalciferol), doxercalciferol and calcipotriene.^ Both are used in over-the-counter vitamin D supplements, but the form available by prescription in the United States is vitamin D 2 .
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ This appears to be a rare form, but is the one used in some vitamin D supplements.
  • eMJA: Vitamin D intake and vitamin D status of Australians 11 September 2009 3:03 UTC www.mja.com.au [Source type: Academic]

^ Both vitamin D 2 and D 3 are used for human nutritional supplementation, and pharmaceutical forms include calcitriol (1alpha, 25-dihydroxycholecalciferol), doxercalciferol and calcipotriene .

[22] .In humans, D3 is as effective as D2 in vitamin D hormone activity in circulation,[23] although others state that D3 is more effective than D2.^ In most mammals , including humans, D 3 is more effective than D 2 at increasing the levels of vitamin D hormone in circulation.

^ Vitamin D3 is also far more effective than D2.
  • The Heart Scan Blog: Prescription vitamin D 11 September 2009 3:03 UTC heartscanblog.blogspot.com [Source type: FILTERED WITH BAYES]

^ Vitamin D is an essential part of the endocrine system as it controls several of the adrenal hormones, growth of cells, production of enzymes and has other direct genomic functions.
  • Vitamin D 28 January 2010 2:02 UTC www.squidoo.com [Source type: FILTERED WITH BAYES]

[24] .However, in some species, such as rats, vitamin D2 is more effective than D3.^ However, some say that D 3 is more effective.
  • What Is Vitamin D? What Are The Benefits Of Vitamin D? 2 February 2010 18:56 UTC www.medicalnewstoday.com [Source type: Academic]

^ Animal experiments, specifically on rats, indicate that D 2 is more effective than D 3 .
  • What Is Vitamin D? What Are The Benefits Of Vitamin D? 2 February 2010 18:56 UTC www.medicalnewstoday.com [Source type: Academic]

^ However, some foods are better sources of vitamin D than others.

[25]

Biochemistry

.Vitamin D is a prohormone, meaning that it has no hormone activity itself, but is converted to the active hormone 1,25-D through a tightly regulated synthesis mechanism.^ The liver and kidney help convert vitamin D to its active hormone form [ 3 ].
  • Vitamin D -- To be free from influenza and many diseases 28 January 2010 2:02 UTC www.allanstime.com [Source type: Academic]

^ Vitamin D is the building block of the hormone calcitriol which works synergistically with PTH. Vitamin D is modified by the liver to become 25-hydroxyvitamin D (also known as 25(OH)D).
  • Bones, Vitamin D, and Calcium 28 January 2010 2:02 UTC www.veganhealth.org [Source type: Academic]

^ Many of the biological effects of 1,25(OH) 2 D are mediated through a nuclear transcription factor known as the vitamin D receptor (VDR) (4) .
  • Linus Pauling Institute at Oregon State University 28 January 2010 2:02 UTC lpi.oregonstate.edu [Source type: Academic]

.Production of vitamin D in nature always appears to require the presence of some UV light; even vitamin D in foodstuffs is ultimately derived from organisms, from mushrooms to animals, which are not able to synthesize it except through the action of sunlight at some point in the synthetic chain.^ Vitamin D3 is cholecalciferol derived from animal products.

^ However, UV-C is present in some lights.

^ Ultimately however, all vitamin D in the food-chain begins with some action of an organism with sunlight.
  • Just How Important Is Vitamin D? – Fitness Spotlight : Fitness Spotlight 2 February 2010 18:56 UTC www.fitnessspotlight.com [Source type: FILTERED WITH BAYES]

For example, fish contain vitamin D only because they ultimately exist on calories from ocean algae which synthesize vitamin D in shallow waters from the action of solar UV.[citation needed]

Production in the skin

.
The epidermal strata of the skin.
^ The epidermal strata of the skin.

^ File:Skinlayers.png The epidermal strata of the skin.

Production is greatest in the stratum basale (colored red in the illustration) and stratum spinosum (colored orange).
.The skin consists of two primary layers: the inner layer called the dermis, composed largely of connective tissue, and the outer, thinner epidermis.^ The skin consists of two primary layers: the inner layer called the dermis , composed largely of connective tissue , and the outer thinner epidermis .

^ Copper is also involved in the proper processing of collagen (the most abundant protein in the body) and thus, is important in skin, bone, and connective tissue production.

^ Because vitamin D can be made in the skin, it should not strictly be called a vitamin, and some nutritional texts refer to the substance as a prohormone and to the two forms as cholecalciferol (D 3 ) or ergocalciferol (D 2 ).
  • Chapter 8. Vitamin D 28 January 2010 2:02 UTC www.fao.org [Source type: Academic]

The epidermis consists of five strata; from outer to inner they are: the stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, and stratum basale.
.Cholecalciferol is produced photochemically in the skin from 7-dehydrocholesterol; 7-dehydrocholesterol is produced in relatively large quantities in the skin of most vertebrate animals, including humans.^ Vitamin D 3 is produced photochemically in the skin from 7-dehydrocholesterol .

^ Vitamin D 3 is produced photochemically in the skin from 7-dehydrocholesterol.

^ Under normal circumstances, ample quantities of 7-dehydrocholesterol (about 25-50 mg / cm 2 of skin) are available in the stratum spinosum and stratum basale of human skin to meet the body's vitamin D requirements, [4] and melanin content does not alter the amount of vitamin D that can be produced.

.The few exceptions are some bat species, , cats, and dogs,[13] which produce little vitamin D.[26] Apes consume vitamin D by grooming which is proposed as a reason to think furry hominid ancestors were adapted to doing the same and that early humans were adapted to oral intake of vitamin D.[27] Serum concentrations of > 25(OH)D concentration > 50 nmol/L are sufficient levels in the domestic cat,[28]normal 25(OH)D levels in domestic dogs are about 70–95 nmol/L[29] In a sample of wild felid in zoos Pallas's Cat was the only feline in the study receiving a diet that was slightly deficient in vitamin D, cheetahs and lions had the highest levels of both metabolites,though their diets did not contain the highest level of the vitamin[30] Living in an environment without sunlight and ingesting no vitamin D, the naked mole rat appear to be naturally cholecalciferol (DJ-deficient.^ However, did dementia cause the low vitamin D levels or did low 25 (OH)D contribute to the dementia?
  • Questions and Answers on Vitamin D (July 2008) Townsend Letter for Doctors & Patients 28 January 2010 2:02 UTC www.townsendletter.com [Source type: FILTERED WITH BAYES]

^ Rickets develop in children with vitamin D deficiency due to a vitamin D-deficient diet, a lack of sunlight, or both.
  • Vitamin D: MedlinePlus Supplements 28 January 2010 2:02 UTC www.nlm.nih.gov [Source type: Academic]
  • Vitamin D 28 January 2010 2:02 UTC www.hoptechno.com [Source type: Academic]
  • Susan G. Komen for the Cure | Understanding Breast Cancer | Complementary Therapies | Vitamin D 2 February 2010 18:56 UTC ww5.komen.org [Source type: Academic]

^ One can therefore be 25 (OH)D deficient and have normal serum calcitriol levels.
  • PaNu - PāNu Blog - Vitamin D 28 January 2010 2:02 UTC www.paleonu.com [Source type: General]

.Serum 25-OH vitamin D levels are undetectable[31] interestingly the naked mole rat is resistant to aging and maintains a youthful vascular function[32] as would be expected in the longest lived of all rodents,[33] it almost never gets cancer and remains youthful, not showing the typical age-associated acceleration in mortality risk that characterizes every other known mammalian species despite living 9 times longer than similarly sized mice.^ However, colorectal cancer mortality was inversely related to serum 25(OH)D concentrations.
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]
  • Vitamin D 28 January 2010 2:02 UTC www.hoptechno.com [Source type: Academic]

^ Serum levels of calcidiol (25-hydroxy-vitamin D) are typically used to diagnose vitamin D overdose.

^ Levels of 1,25(OH)2D do not typically decrease until vitamin D deficiency is severe.
  • Vitamin D - Medpedia 28 January 2010 2:02 UTC wiki.medpedia.com [Source type: Academic]
  • Vitamin D Analogues 28 January 2010 2:02 UTC www.globalrph.com [Source type: Academic]

They may be the first reported mammal showing negligible senescence over the majority of their long lifespan. .Moreover breeding females show no reduction in fertility even in their third decade[34] This is not, of course, any indication of vitamin D being the 'cause' of aging but a example of the power of natural selection which, by acting on heritable traits that make it more likely for an organism to survive and successfully reproduce, makes that organism's decendants more common in a population over successive generations.^ Cancer patients with high levels of vitamin D more likely to survive .

^ Vitamin D and chronic widespread pain in a white middle-aged British population: evidence from a cross-sectional population survey.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ A recent meta-analysis found that use of vitamin D supplements was associated with a reduction in overall mortality from any cause by a statistically significant 7% [ 86 , 87 ].
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

.A genetically modified mouse that was thought to be a model of premature aging turned out to be aging from an excess of vitamin D [35] Again this is an example of what happens when vitamin D homeostasis,which depends on multiple dynamic equilibria adjustment and regulation mechanisms, is disturbed[36][37] as natural selection maximizes fitness not longevity.^ It turns out that muscles, along with most other tissues in the body have vitamin D receptors (VDRs) .
  • A Closer Look at Vitamin D | Eat. Move. Improve. 2 February 2010 18:56 UTC www.eatmoveimprove.com [Source type: FILTERED WITH BAYES]

^ Never in a million years would I have thought all these symptoms could possibly be related, but it turns out that they were.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ Despite the importance of the sun to vitamin D synthesis, it is prudent to limit exposure of skin to sunlight [36] and UV radiation from tanning beds [37].

.In most animals the highest concentrations of 7-dehydrocholesterol are found in the epidermal layer of skin, specifically in the stratum basale and stratum spinosum.^ The highest concentrations of 7-dehydrocholesterol are found in the epidermal layer of skin, specifically in the stratum basale and stratum spinosum.

^ The two most important factors that govern the generation of pre-vitamin D 3 are the quantity (intensity) and quality (appropriate wavelength) of the UVB irradiation reaching the 7-dehydrocholesterol deep in the stratum basale and stratum spinosum.

^ Under normal circumstances, ample quantities of 7-dehydrocholesterol (about 25-50 mg / cm 2 of skin) are available in the stratum spinosum and stratum basale of human skin to meet the body's vitamin D requirements, [4] and melanin content does not alter the amount of vitamin D that can be produced.

[14] .The production of pre-vitamin D3 is therefore greatest in these two layers, whereas production in the other layers is less.^ The production of pre-vitamin D 3 is therefore greatest in these two layers, whereas production in the other layers is reduced.

^ The product is pre-vitamin D 3 .

^ On the other hand, adolescents who drink milk and eat cereal are less likely to be deficient on the vitamin.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

.Synthesis in the skin involves UVB radiation, which effectively penetrates only the epidermal layers of skin.^ Synthesis in the skin involves UVB radiation which effectively penetrates only the epidermal layers of skin.

^ UVB radiation does not penetrate glass, so exposure to sunshine indoors through a window does not produce vitamin D [35].

^ Exposure to lamps that emit UVB radiation is an excellent source for producing vitamin D3 in the skin and is especially efficacious in patients with fat malabsortion syndromes.” .

.While 7-dehydrocholesterol absorbs UV light at wavelengths between 270–300 nm, optimal synthesis occurs in a narrow band of UVB spectra between 295-300 nm.^ Dehydrocholesterol absorbs UV light most effectively at wavelengths between 270–290 nm and thus the production of vitamin D 3 will only occur at those wavelengths.

^ In skin, 7-dehydrocholesterol is converted to pre-vitamin D3 by a narrow band of solar ultraviolet radiation (290-320 nm) which undergoes isomerisation in a temperature-dependent manner to vitamin D 3 .
  • NHMRC Nutrient Reference Values - Nutrients vitamin D 28 January 2010 2:02 UTC www.nrv.gov.au [Source type: Academic]

^ Vitamin D 3 is derived from animal sources and is made in the skin when 7-dehydrocholesterol reacts with UVB ultraviolet light at wavelengths between 270–290 nm.

Peak isomerization is found at 297 nm. This narrow segment is sometimes referred to as D-UV.[15] .The two most important factors that govern the generation of pre-vitamin D3 are the quantity (intensity) and quality (appropriate wavelength) of the UVB irradiation reaching the 7-dehydrocholesterol deep in the stratum basale and stratum spinosum.^ Vitamin C is one of the most important of all vitamins.

^ Vitamin D is the most important nutrient.
  • Vitamin D - Paulding.com 28 January 2010 2:02 UTC www.paulding.com [Source type: General]

^ The two most important factors that govern the generation of pre-vitamin D 3 are the quantity (intensity) and quality (appropriate wavelength) of the UVB irradiation reaching the 7-dehydrocholesterol deep in the stratum basale and stratum spinosum.

[14]
.A critical determinant of vitamin D3 production in the skin is the presence and concentration of melanin.^ A critical determinant of vitamin D 3 production in the skin is the presence and concentration of melanin .

^ The radiation that converts vitamin D in the skin is the same wavelength that causes sunburn, so careful application of sunscreen can inhibit vitamin D production.

^ "Skin pigment acts as a natural sunscreen—it protects the skin, but also reduces vitamin D production," Harris says.
  • Vitamin D and Diabetes | Diabetes Forecast Magazine 2 February 2010 18:56 UTC forecast.diabetes.org [Source type: Academic]

.Melanin functions as a light filter in the skin, and therefore the concentration of melanin in the skin is related to the ability of UVB light to penetrate the epidermal strata and reach the 7-dehydrocholesterol-containing stratum basale and stratum spinosum.^ Skin contains a cholesterol derivative, 7-dehydrocholesterol.
  • Avoid Flu Shots, Take Vitamin D Instead by Donald W. Miller, Jr., MD 28 January 2010 2:02 UTC www.lewrockwell.com [Source type: FILTERED WITH BAYES]

^ The highest concentrations of 7-dehydrocholesterol are found in the epidermal layer of skin, specifically in the stratum basale and stratum spinosum.

^ Melanin functions as a light filter in the skin, and therefore the concentration of melanin in the skin is related to the ability of UVB light to penetrate the epidermal strata and reach the 7-dehydrocholesterol-containing stratum basale and stratum spinosum.

.Under normal circumstances, ample quantities of 7-dehydrocholesterol (about 25-50 µg/cm² of skin) are available in the stratum spinosum and stratum basale of the skin to meet the body's vitamin D requirements,[14] and melanin content does not alter the amount of vitamin D that can be produced.^ What vitamin, and the only one, does your skin produce?
  • Why vitamin D may prevent H1N1 | Prevention | Get Healthy | Best Health 2 February 2010 18:56 UTC www.besthealthmag.ca [Source type: General]

^ The body makes 25-D3 from 7-dehydrocholesterol.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]

^ Vitamin B6 (pyridoxine) is required for the body to produce serotonin and norepinephrine.
  • Vitamin D | LIVESTRONG.COM 28 January 2010 2:02 UTC www.livestrong.com [Source type: FILTERED WITH BAYES]

[38] .Thus, individuals with higher skin melanin content will simply require more time in sunlight to produce the same amount of vitamin D as individuals with lower melanin content.^ Sunlight and vitamin D requirements .
  • What Is Vitamin D? What Are The Benefits Of Vitamin D? 2 February 2010 18:56 UTC www.medicalnewstoday.com [Source type: Academic]

^ Vitamin D3 is produced in the skin during exposure to sunlight.
  • Sundays Tanning Resort Blog - Virginia Beach Tanning Salons 28 January 2010 2:02 UTC tanstr.com [Source type: Academic]
  • Just “D” Facts about Vitamin D 2 February 2010 18:56 UTC justdfacts.wordpress.com [Source type: Academic]

^ Supplements of the vitamin D are not required by individuals who get plenty of exposure to sunlight.

.The amount of time an individual requires to produce a given amount of vitamin D may also depend upon the person's distance from the equator and on the season of the year.^ Requirements depend upon the exposure of a persons skin to ultraviolet radiation.

^ Season, geographic latitude , time of day, cloud cover, smog , and sunscreen affect UV ray exposure and vitamin D synthesis in the skin, and it is important for individuals with limited sun exposure to include good sources of vitamin D in their diet.

^ It has been noted that blood pressure is often elevated during the winter season, further distance from the equator, and dark skin pigmentation (all of which are associated with lower exposure to vitamin D via sunlight).
  • Vitamin D - Drugs & Treatments - Revolution Health 28 January 2010 2:02 UTC www.revolutionhealth.com [Source type: Academic]

.In some animals, the presence of fur or feathers blocks the UV rays from reaching the skin.^ If you live in the mid-latitudes or high latitudes, you have little to no access to UV-B rays from some point in autumn to some point in spring.
  • How to Make Sure that You Are Getting Enough Vitamin D for Your Best Health 28 January 2010 2:02 UTC drbenkim.com [Source type: General]

^ A precursor to vitamin D exists naturally in the skin, and exposure to the sun's ultraviolet (UV) rays touches off a chemical process that creates the usable form of the vitamin.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ UV-B rays are the ones that are capable of producing vitamin D in your body by acting on cholesterol found in your skin.
  • How to Make Sure that You Are Getting Enough Vitamin D for Your Best Health 28 January 2010 2:02 UTC drbenkim.com [Source type: General]

.In birds and fur-bearing mammals, vitamin D is generated from the oily secretions of the skin deposited onto the fur and obtained orally during grooming.^ Vitamin D can be obtained from food, including oily fish and eggs, but it is harder for the body to obtain enough from these sources and consumption of these products in the UK has dramatically declined.

^ Vitamin D that we obtain through the diet seems to be less effective than the vitamin that is generated in the sun,” she says.

^ Fish, unlike mammals, birds and reptiles, do not respond to sunlight and rely on vitamin D found in phytoplankton and other fish.

[39]
.In 1923, Harry Goldblatt and Katherine Soames established that when 7-dehydrocholesterol (a precursor of vitamin D in the skin) is irradiated with light, a form of a fat-soluble vitamin is produced.^ Fat soluble vitamins .
  • Fat Soluble Vitamins: Vitamin A, D, E, & K in Dogs 28 January 2010 2:02 UTC www.peteducation.com [Source type: Academic]

^ Vitamin D is a fat-soluble vitamin.
  • Just How Important Is Vitamin D? – Fitness Spotlight : Fitness Spotlight 2 February 2010 18:56 UTC www.fitnessspotlight.com [Source type: FILTERED WITH BAYES]

^ Vitamin E Vitamin E is the third of the fat soluble vitamins.
  • Fat Soluble Vitamins: Vitamin A, D, E, & K in Dogs 28 January 2010 2:02 UTC www.peteducation.com [Source type: Academic]

.Alfred Fabian Hess and Mildred Weinstock further substantiated that "[sun]light equals vitamin D".[40] Adolf Windaus, at the University of Göttingen in Germany, received the Nobel Prize in Chemistry in 1928, for his work on the constitution of sterols and their connection with vitamins.^ Because the newly discovered substance was the fourth vitamin identified, it was called vitamin D. [13] The 1928 Nobel Prize in Chemistry was awarded to Adolf Windaus , who discovered the steroid, 7-dehydrocholesterol, the precursor of vitamin D. .

^ Some plants and fungi convert ergosterol (a plant sterol) into Vitamin D2 (ergocalciferol) in response to light and these plants can then be a minor nutritional source of calciferol for humans.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

^ In one study, vitamin D was found to be better than light therapy in the treatment of SAD. Further studies are necessary to confirm these findings.
  • Vitamin D: MedlinePlus Supplements 28 January 2010 2:02 UTC www.nlm.nih.gov [Source type: Academic]

[41] In 1930s, he clarified further the chemical structures of the vitamins D.

Synthesis mechanism (form 3)

7-dehydrocholesterol, a derivative of cholesterol, is photolyzed by ultraviolet light in 6-electron conrotatory electrocyclic reaction. The product is pre-vitamin D3.
Reaction-Dehydrocholesterol-PrevitaminD3.png
Pre-vitamin D3 then spontaneously isomerizes to Vitamin D3 in a antarafacial hydride [1,7] Sigmatropic shift. .At room temperature the transformation of previtamin-D3 to vitamin D3 takes about 12 days to complete.^ I've been taking 2000 IU a day for about a week.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ Sunshine: With exposure to ultraviolet light the skin synthesizes vitamin D. It is estimated that 20 minutes, with face and arms exposed, will stimulate about 200 I.U. per day.

^ I am taking prescription vitamin D for 13 days, a green gel pill.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

[13]
Reaction-PrevitaminD3-VitaminD3.png
Whether it is made in the skin or ingested, vitamin D.3 (cholecalciferol) is then hydroxylated in the liver to 25-hydroxycholecalciferol (25(OH)D3 or calcidiol) by the enzyme 25-hydroxylase produced by hepatocytes.^ In the liver cholecalciferol is hydroxylated at the 25 position by a specific D 3 -25-hydroxylase generating 25-hydroxy-D 3 [25-(OH)D 3 ] which is the major circulating form of vitamin D. Conversion of 25-(OH)D 3 to its biologically active form, calcitriol, occurs through the activity of a specific D 3 -1-hydroxylase present in the proximal convoluted tubules of the kidneys, and in bone and placenta.

^ Milk used to make cheese or yogurt is usually not fortified with vitamin D. Human milk contains the 25 hydroxycholecalciferol form of D probably because the liver in infants is not that functional for the first hydroxylation of cholecalciferol.

^ Vitamin D is initially hydroxylated in the 25 position by the hepatic microsomal and/or mitochondrial enzyme vitamin D 25-hydroxylase.
  • Vitamin D Deficiency and Related Disorders: eMedicine Endocrinology 28 January 2010 2:02 UTC emedicine.medscape.com [Source type: Academic]

.This hydroxylation reaction occurs in the endoplasmic reticulum and requires NADPH, O2 and Mg2+ yet it is not a cytochrome P450 enzyme.^ Same with vitamin D. It is possible that blood levels could be low or normal, yet untoward reactions could be occurring in other tissues, such as brain tissue.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Retinal is reduced to retinol by retinaldehyde reductase, an NADPH requiring enzyme within the intestines.

^ The most important reaction requiring ascorbate as a cofactor is the hydroxylation of proline residues in collagen.

.Once made the product is stored in the hepatocytes until it is needed and then can be released into the plasma where it will be bound to an α-globulin.^ (OH)D 3 or calcidiol ) and stored until it is needed.

^ Following this conversion, the hormonally active form of vitamin D is released into the circulation, and by binding to a carrier protein in the plasma , vitamin D binding protein (VDBP), it is transported to various target organs.

^ Vitamin D (hereafter "D" represents D 2 or D 3 ) made in the skin or ingested in the diet can be stored in and then released from fat cells.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

.25-hydroxycholecalciferol is then transported to the proximal tubules of the kidneys where it can be hydroxylated by one of two enzymes to different forms of vitamin D, one of which is active vitamin D (1,25-OH D) and another which is inactive vitamin D (24,25-OH D).^ The liver and kidney help convert vitamin D to its active hormone form [ 3 ].
  • Vitamin D -- To be free from influenza and many diseases 28 January 2010 2:02 UTC www.allanstime.com [Source type: Academic]

^ Vitamin D occurs in two forms.
  • NHMRC Nutrient Reference Values - Nutrients vitamin D 28 January 2010 2:02 UTC www.nrv.gov.au [Source type: Academic]

^ This form of vitamin D is biologically inactive and must be converted in the kidneys by 25-hydroxyvitamin D-1 -hydroxylase (1-OHase) to the biologically active form — 1,25-dihydroxyvitamin D [1,25(OH) 2 D].
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

.The enzyme 1α-hydroxylase which is activated by parathyroid hormone (and additionally by low calcium or phosphate) forms the main biologically active vitamin D hormone with a C1 hydroxylation forming 1,25-dihydroxycholecalciferol (1,25(OH)2D3, also known as calcitriol).^ D3, the active form of vitamin D, was reclassified as a hormone that controlled calcium metabolism.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]

^ Vitamin D is initially hydroxylated in the 25 position by the hepatic microsomal and/or mitochondrial enzyme vitamin D 25-hydroxylase.
  • Vitamin D Deficiency and Related Disorders: eMedicine Endocrinology 28 January 2010 2:02 UTC emedicine.medscape.com [Source type: Academic]

^ The second occurs primarily in the kidney and forms the physiologically active 1,25-dihydroxyvitamin D [1,25(OH) 2 D], also known as calcitriol [ 3 ].
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

.A separate enzyme hydroxylates the C24 atom forming 24R,25(OH)2D3 when 1α-hydroxylase is not active, this inactivates the molecule from any biological activity.^ This form of vitamin D is biologically inactive and must be converted in the kidneys by 25-hydroxyvitamin D-1 -hydroxylase (1-OHase) to the biologically active form — 1,25-dihydroxyvitamin D [1,25(OH) 2 D].
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ Once vitamin D is produced in the skin or consumed in food, it is convered in the liver and kidney to form 1,25 dihydroxyvitamin D, (1,25(OH) 2 D) the physiologically active form of vitamin D (when "D" is used without a subscript it refers to either D 2 or D 3 ).

^ In the liver cholecalciferol is hydroxylated at the 25 position by a specific D 3 -25-hydroxylase generating 25-hydroxy-D 3 [25-(OH)D 3 ] which is the major circulating form of vitamin D. Conversion of 25-(OH)D 3 to its biologically active form, calcitriol, occurs through the activity of a specific D 3 -1-hydroxylase present in the proximal convoluted tubules of the kidneys, and in bone and placenta.

.Calcitriol is represented below right (hydroxylated Carbon 1 is on the lower ring at right, hydroxylated Carbon 25 is at the upper right end).^ Calcitriol is represented below right (hydroxylated Carbon 1 is on the lower ring at right, hydroxylated Carbon 25 is at the upper right end).

^ Note extra OH groups at upper right and lower left.

^ The much more high-potency active form of Vit D has an extra hydroxyl group and is 1,25 (OH)D or calcitriol.
  • PaNu - PāNu Blog - Vitamin D 28 January 2010 2:02 UTC www.paleonu.com [Source type: General]

Reaction-VitaminiD3-Calcitriol.png

Mechanism of action

.After vitamin D is produced in the middle layers of skin or consumed in food, it is converted in the liver and kidney to form 1,25 dihydroxyvitamin D, (1,25(OH)2D), the physiologically active form of vitamin D (when "D" is used without a subscript it refers to either D2 or D3).^ The liver and kidney help convert vitamin D to its active hormone form [ 3 ].
  • Vitamin D -- To be free from influenza and many diseases 28 January 2010 2:02 UTC www.allanstime.com [Source type: Academic]

^ Once vitamin D is produced in the skin or consumed in food, it requires chemical conversion in the liver and kidney to form 1,25 dihydroxyvitamin D, the physiologically active form of vitamin D. Active vitamin D functions as a hormone because it sends a message to the intestines to increase the absorption of calcium and phosphorus [ 3 ].
  • Vitamin D -- To be free from influenza and many diseases 28 January 2010 2:02 UTC www.allanstime.com [Source type: Academic]

^ Sunlight is an important way for our skin to convert vitamin D to its active form.

.This physiologically active form of vitamin D is known as calcitriol.^ D3, the active form of vitamin D, was reclassified as a hormone that controlled calcium metabolism.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

^ The liver and kidney help convert vitamin D to its active hormone form [ 3 ].
  • Vitamin D -- To be free from influenza and many diseases 28 January 2010 2:02 UTC www.allanstime.com [Source type: Academic]

^ Calciferol is the most active form of vitamin D. Other forms are relatively inactive in the body.
  • Vitamin D -- To be free from influenza and many diseases 28 January 2010 2:02 UTC www.allanstime.com [Source type: Academic]

.Following this conversion, calcitriol is released into the circulation, and by binding to a carrier protein in the plasma, vitamin D-binding protein (VDBP), it is transported to various target organs.^ Bioavailability of D metabolites D-Binding Protein is the major transporter of vitamin D metabolites in the circulation.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]

^ Free hormone crosses the plasma membrane and interacts with a specific nuclear receptor known as the vitamin D receptor, a DNA-binding, zinc-finger protein with a molecular weight of 55,000 ( 4 ).
  • Chapter 8. Vitamin D 28 January 2010 2:02 UTC www.fao.org [Source type: Academic]

^ (DHCC), the most active form of vitamin D, functions to: » Increase the absorption of calcium from the intestines by stimulating the synthesis of calcium-binding protein.

[12]
.The physiologically active form of vitamin D mediates its biological effects by binding to the vitamin D receptor (VDR), which is principally located in the nuclei of target cells.^ The vitamin D receptor, or VDR, is a nuclear receptor.
  • PaNu - PāNu Blog - Vitamin D 28 January 2010 2:02 UTC www.paleonu.com [Source type: General]

^ Retinol is the most active form of vitamin A. .
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Many cells, including breast, brain, prostate, and colon tissue, as well as immune cells, have receptors which can be activated by 1,25-dihydroxyvitamin D. † 13 Cell studies have shown that vitamin D, in the form of cholecalciferol, supports normal prostate cell replication and division.

[12] .The binding of calcitriol to the VDR allows the VDR to act as a transcription factor that modulates the gene expression of transport proteins (such as TRPV6 and calbindin), which are involved in calcium absorption in the intestine.^ In the intestinal epithelium, calcitriol functions as a steroid hormone in inducing the expression of calbindinD 28K , a protein involved in intestinal calcium absorption.

^ (OH) 2 D enhances intestinal calcium absorption in the small intestine by interacting with the vitamin D receptor–retinoic acid x-receptor complex (VDR-RXR) to enhance the expression of the epithelial calcium channel (transient receptor potential cation channel, subfamily V, member 6 [TRPV6]) and calbindin 9K, a calcium-binding protein (CaBP).
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ This ligand-receptor complex binds to a specific vitamin D-responsive element and, with associated transcription factors (e.g., retinoid X receptor), enhances transcription of mRNAs which code for calcium-transporting proteins, bone matrix proteins, or cell cycle-regulating proteins ( 5 ).
  • Chapter 8. Vitamin D 28 January 2010 2:02 UTC www.fao.org [Source type: Academic]

.The vitamin D receptor belongs to the nuclear receptor superfamily of steroid/thyroid hormone receptors, and VDRs are expressed by cells in most organs, including the brain, heart, skin, gonads, prostate, and breast.^ Bone and vascular smooth muscle have vitamin D receptors, so do heart muscle cells.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Vitamin D is also a classified steroid hormone.
  • Bodybuilding.com - Vitamin D Information and Product Listing! Vitamin D FAQ! 28 January 2010 2:02 UTC www.bodybuilding.com [Source type: FILTERED WITH BAYES]

^ The vitamin D receptor, or VDR, is a nuclear receptor.
  • PaNu - PāNu Blog - Vitamin D 28 January 2010 2:02 UTC www.paleonu.com [Source type: General]

.VDR activation in the intestine, bone, kidney, and parathyroid gland cells leads to the maintenance of calcium and phosphorus levels in the blood (with the assistance of parathyroid hormone and calcitonin) and to the maintenance of bone content.^ That hormone, in turn, prompts the intestines to transfer calcium from food to the blood.
  • Unraveling the Enigma of Vitamin D - Text View 28 January 2010 2:02 UTC www.beyonddiscovery.org [Source type: Academic]

^ Vitamin D controls the levels of calcium in the blood.

^ Vitamin D is important for bone health because it regulates calcium and phosphorus levels in the blood.
  • Vitamin D: What Is Vitamin D, Why We Need It, How To Get It 28 January 2010 2:02 UTC www.savvyvegetarian.com [Source type: Academic]

[42]
.The VDR is known to be involved in cell proliferation and differentiation.^ Many genes encoding proteins that regulate cell proliferation, differentiation, and apoptosis are modulated in part by vitamin D [3,5,8,9].

^ In addition to immune cells that may control cancer promotion, cells of tissues susceptible to cancer also express the VDR. Vitamin D binds to the VDR and new proteins are synthesized that control cell differentiation, proliferation and recognition of adjacent cells, all functions important in the development of cancer.
  • PaNu - PāNu Blog - Vitamin D 28 January 2010 2:02 UTC www.paleonu.com [Source type: General]

^ Many genes encoding proteins that regulate cell proliferation, differentiation, and apoptosis are modulated in part by vitamin D [ 3 , 5 , 8 , 9 ].
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

.Vitamin D also affects the immune system, and VDRs are expressed in several white blood cells, including monocytes and activated T and B cells.^ Many cells, including breast, brain, prostate, and colon tissue, as well as immune cells, have receptors which can be activated by 1,25-dihydroxyvitamin D. † 13 Cell studies have shown that vitamin D, in the form of cholecalciferol, supports normal prostate cell replication and division.

^ D deficiency and mortality, with the vitamins active form (1,25-dihydroxyvitamin D) linked to a range of effects including control of inflammatory compounds, regulating immune health and blood pressure, or reducing arterial hardening ...

^ Vitamin D receptors are present on cells responsible for both the innate and adaptive immune response, including T cells, B cells, macrophages, and dendritic cells.
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

[22]
.Apart from VDR activation, various alternative mechanisms of action are known.^ While some complementary and alternative techniques have been studied scientifically, high-quality data regarding safety, effectiveness, and mechanism of action are limited or controversial for most therapies.
  • Vitamin D - Drugs & Treatments - Revolution Health 28 January 2010 2:02 UTC www.revolutionhealth.com [Source type: Academic]
  • Vitamin D | LIVESTRONG.COM 28 January 2010 2:02 UTC www.livestrong.com [Source type: FILTERED WITH BAYES]

.An important one of these is its role as a natural inhibitor of signal transduction by hedgehog (a hormone involved in morphogenesis).^ Iodine is required for the synthesis of the thyroid hormones and thus plays an important role in the regulation of energy metabolism via thyroid hormone functions.

^ Zinc interacts with the hormone insulin to ensure proper function and thus this trace mineral has an important role in regulation of blood glucose levels via insulin action.

[43][44]

Nutrition

Milk and cereal grains are often fortified with vitamin D.
.Vitamin D is naturally produced by the human body when exposed to direct sunlight.^ Your body makes vitamin D when it's exposed to sunlight.
  • Vitamin D -- Why You Are Probably NOT Getting Enough 28 January 2010 2:02 UTC www.ultrawellness.com [Source type: General]

^ Vitamin D3 is produced in your skin when exposed to sunlight.
  • Vitamin D – A Gene-Regulating Super Nutrient | Health Tips 28 January 2010 2:02 UTC www.wellnessresources.com [Source type: Academic]

^ The body produces vitamin D3 when the skin is exposed to ultraviolet-B (U...
  • Vitamin D | LIVESTRONG.COM 28 January 2010 2:02 UTC www.livestrong.com [Source type: FILTERED WITH BAYES]

.Season, geographic latitude, time of day, cloud cover, smog, and sunscreen affect UV ray exposure and vitamin D synthesis in the skin, and it is important for individuals with limited sun exposure to include good sources of vitamin D in their diet.^ Season, latitude, and ability of sunlight to promote synthesis of vitamin D3 in skin.

^ Sunshine is a significant source of vitamin D because UV rays from sunlight trigger vitamin D synthesis in the skin [ 1-2 ].
  • Vitamin D -- To be free from influenza and many diseases 28 January 2010 2:02 UTC www.allanstime.com [Source type: Academic]

^ Individuals with limited sun exposure need to include good sources of vitamin D in their diet or take a supplement.
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]
  • Vitamin D 28 January 2010 2:02 UTC www.hoptechno.com [Source type: Academic]

.Extra vitamin D is also recommended for older adults and people with dark skin.^ Gloth FM 3rd, Smith CE, Hollis BW, Tobin JD. Functional improvement with vitamin D replenishment in a cohort of frail, vitamin D-deficient older people.
  • Peak Athletic Performance & Vitamin D 28 January 2010 2:02 UTC impachealth.com [Source type: Academic]

^ Individuals with darkly pigmented skin who are unable to get adequate sun exposure and/or consume recommended amounts of vitamin D may benefit from a vitamin D supplement.
  • Vitamin D - Medpedia 28 January 2010 2:02 UTC wiki.medpedia.com [Source type: Academic]

^ Preventing fractures among older people living in institutional care: a pragmatic randomised double blind placebo controlled trial of vitamin D supplementation.
  • Vitamin D | ThirdAge Articles 28 January 2010 2:02 UTC www.thirdage.com [Source type: Academic]

Individuals having a high risk of deficiency should consume 25 μg (1000 IU) of vitamin D daily to maintain adequate blood concentrations of 25-hydroxyvitamin D.[2]
.As civilization and the Industrial Revolution enabled humans to work indoors and wear more clothes when outdoors, these cultural changes reduced natural production of vitamin D and caused deficiency diseases.^ People also spend less time outdoors and wear more clothing.
  • NHMRC Nutrient Reference Values - Nutrients vitamin D 28 January 2010 2:02 UTC www.nrv.gov.au [Source type: Academic]

^ Vitamin D deficiency does not cause rickets.
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

^ "Vitamin D deficiency and risk of cardiovascular disease".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

.In many countries, such foods as milk, yogurt, margarine, oil spreads, breakfast cereal, pastries, and bread are fortified with vitamin D2 and/or vitamin D3, to minimize the risk of vitamin D deficiency.^ Milk, vitamin D fortified, 1 cup .
  • Vitamin D - Medpedia 28 January 2010 2:02 UTC wiki.medpedia.com [Source type: Academic]

^ WHERE TO FIND VITAMIN D Cod liver oil, oily fish such as mackerel and salmon, liver, eggs and fortified foods such as cereals, margarine and powdered milk.

^ "Vitamin D deficiency and risk of cardiovascular disease".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

[45] .In the United States and Canada, for example, fortified milk typically provides 100 IU per cup, or a quarter of the estimated adequate intake for adults over age 50.[2] A 1992 study, however, found that the actual vitamin D content of milk varies widely.^ For example, almost all of the U.S. milk supply is fortified with 100 IU/cup of vitamin D (25% of the Daily Value or 50% of the AI level for ages 14-50 years).
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

^ The vitamin D content of fortified milk and infant formula.
  • Vitamin D Deficiency and Related Disorders: eMedicine Endocrinology 28 January 2010 2:02 UTC emedicine.medscape.com [Source type: Academic]
  • Vitamin D & HIV 28 January 2010 2:02 UTC www.natap.org [Source type: Academic]

^ As stated above, the vitamin D content of human milk is low ( 16 ).
  • Chapter 8. Vitamin D 28 January 2010 2:02 UTC www.fao.org [Source type: Academic]

.Supplementation of 100 IU (2.5 microgram) vitamin D3 raises blood calcidiol levels by 2.5 nmol/litre (1 ng/ml).^ Vitamin D controls the levels of calcium in the blood.

^ In July 2008 I was tested for Vitamin D and the level was 22 ng/ml.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Vitamin D 1000 IU, 100 Softgels .
  • Vitamin D Supplements at the Lowest Prices! 2 February 2010 18:56 UTC www.a1supplements.com [Source type: General]

[46]

Natural sources

Fatty fish, such as salmon, are natural sources of vitamin D.
Natural sources of vitamin D include:[2]
  • Fatty fish species, such as:
    • Herring, 85 g (3 ounces (oz)) provides 1383 IU
    • Catfish, 85 g (3 oz) provides 425 IU
    • Salmon, cooked, 100 g (3.5 oz]) provides 360 IU
    • Mackerel, cooked, 100 g (3.5 oz]), 345 IU
    • Sardines, canned in oil, drained, 50 g (1.75 oz), 250 IU
    • Tuna, canned in oil, 85 g (3 oz), 200 IU
    • Eel, cooked, 100 g (3.5 oz), 200 IU
    • Fish liver oils, such as cod liver oil, 1 Tbs. (15 ml) provides 1,360 IU (one IU equals 25 ng)
  • A whole egg, provides 20 IU
  • Beef liver, cooked, 100 g (3.5 oz), provides 15 IU
.In the United States (U.S.), the 100% Daily Value used for product labels is 800 IU/day (as of new 2009 data) and typical diets provide about 100 IU/day.^ It appears the daily dosage is about 3500 iu a day.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ A meta-analysis evaluated the effect of vitamin D supplementation (using a mean supplementation dosage of about 500 IU daily) on all-cause mortality in 18 randomized controlled trials and found a 7% relative risk reduction for death.
  • Vitamin D Deficiency and Related Disorders: eMedicine Endocrinology 28 January 2010 2:02 UTC emedicine.medscape.com [Source type: Academic]

^ Canada is way ahead of the US in this regard B recommending 1,000 IU of vitamin D per day and providing the opportunity to by lamps that have the needed UVB spectrum.
  • Vitamin D -- To be free from influenza and many diseases 28 January 2010 2:02 UTC www.allanstime.com [Source type: Academic]

.Although milk is usually fortified, the average daily consumption by most Americans is insufficient in obtaining levels of vitamin D recommended by various medical authorities.^ Most Americans get vitamin D through sunshine, fortified milk, and fortified margarine.
  • Bones, Vitamin D, and Calcium 28 January 2010 2:02 UTC www.veganhealth.org [Source type: Academic]

^ Milk, vitamin D fortified, 1 cup .
  • Vitamin D - Medpedia 28 January 2010 2:02 UTC wiki.medpedia.com [Source type: Academic]

^ Fortified foods provide most of the vitamin D in the American diet [ 4 , 26 ].
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

[47] .While adequate intake has been defined as 200 IU/day for ages infant to 50, 400/day for 51-70, and 600/day over 70, the American Academy of Pediatrics argues that these recommendations are insufficient and recommends a minimum of 400 IU, even for infants.^ Note that the American Academy of Pediatrics recommended in November 2008 that the minimum intake for children and adolescents be changed to 400 IU / day.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ For 50-70 years-old, 10mcg daily (400 IU); for 70-years-old, 15micrograms daily (600 IU).
  • Vitamin D | LIVESTRONG.COM 28 January 2010 2:02 UTC www.livestrong.com [Source type: FILTERED WITH BAYES]

^ The RDA for vitamin D is 5 mcg (200 IU) for people aged 1 to 50, and 10 mcg (400 IU) for people over 50.
  • Bones, Vitamin D, and Calcium 28 January 2010 2:02 UTC www.veganhealth.org [Source type: Academic]

[48] .The NIH has set the safe upper limit at 2000 IU, but acknowledges newer data supporting a UL as high as 10,000 IU/day.^ The safe upper limit of vitamin D consumption is 10,000 IU per day ...

^ A safe upper limit is 2,000 IU daily.

^ Upper Limit a mcg b (IU) .
  • Bones, Vitamin D, and Calcium 28 January 2010 2:02 UTC www.veganhealth.org [Source type: Academic]

[49] .Some experts have recommended greatly increasing vitamin D intake.^ It should also be noted that not all researchers agree that vitamin D intakes need to be significantly increased.
  • Bones, Vitamin D, and Calcium 28 January 2010 2:02 UTC www.veganhealth.org [Source type: Academic]

^ Increased intake of vitamin E is recommended in premature infants fed formulas that are low in the vitamin as well as in persons consuming a diet high in polyunsaturated fatty acids.

^ Vitamin D intake increases both calcium and phosphorus absorption.

[50] The Institute Of Medicine is revisiting vitamin D and calcium recommendations with a report expected to be released before the end of summer 2010.[51]

Vegetarian Sources

.Mushrooms exposed to UV light are the only known vegetarian sources of (Vitamin D2).^ UV-B, the only band of light producing vitamin D, is significantly present only midday during summer months in most of the U.S. , the exact time we are advised to avoid sunlight.

^ In 1952, Ronge exposed 120 German schoolchildren to UV lights installed in classrooms and compared them to 120 un-irradiated control children.
  • Peak Athletic Performance & Vitamin D 28 January 2010 2:02 UTC impachealth.com [Source type: Academic]

^ Sunlight is a significant source of vitamin D because UV rays from sunlight trigger vitamin D synthesis in the skin.
  • Vitamin D - Medpedia 28 January 2010 2:02 UTC wiki.medpedia.com [Source type: Academic]

[52][53] .One Californian company offers the common mushroom with 100% RDA of (Vitamin D2) per 3 ounces.^ This range of fortification produces a standard 20 calorie per ounce formula providing between 265 and 660 IU vitamin D per liter.
  • Vitamin D - Medpedia 28 January 2010 2:02 UTC wiki.medpedia.com [Source type: Academic]

^ My level was 15 (I was told normal was 32 - 100) SO, she has prescribed 50,000 units of vitamin D once per month.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ USDA databases compiled in the 1980s list the following foods as rich in vitamin D. The amounts given are for 100 grams or about 3 1/2 ounces.

[15]

Measuring nutritional status

.A blood calcidiol (25-hydroxy-vitamin D) level is a satisfactory way to determine the cumulative effect of sun and diet in relation to vitamin D[54] although serum 25(OH)D levels do not indicate the amount of vitamin D stored in other body tissues.^ Vitamin D controls the levels of calcium in the blood.

^ He then tested their blood for vitamin D, which are measured in 25-hydroxyvitamin D (25-OHD) levels.

^ The 25(OH)D level in the blood was determined weekly for seven weeks.

[55] .A concentration of over 15 ng/ml (>37.5 nmol/L) is recommended.^ The prevalence of serum concentrations of 25(OH)D less than or equal to 15 ng/mL (less than or equal to 37.5 nmol/L) was 10 times greater for the African American women (42.2%) than for the white women (4.2%).

^ In an animal model, concentrations ≤400 ng/mL (≤1,000 nmol/L) were not associated with harm [ 14 ].
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

^ The prevalence of serum concentrations of 25(OH)D ≤15 ng/mL (≤37.5 nmol/L) was 10 times greater for the African American women (42.2%) than for the white women (4.2%).
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

.Higher levels (>30 ng/ml or >75 nmol/L) are proposed by some as desirable for achieving optimum health but there is not enough evidence to support them.^ Higher levels are proposed by some (> 30 ng/ml or > 75 nmol/L) as desirable for overall health and disease prevention [12], but insufficient data are available to support them [13].

^ Higher levels are proposed by some (> 30 ng/ml or > 75 nmol/L) as desirable for overall health and disease prevention [ 12 ], but insufficient data are available to support them [ 13 ].
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

^ Although most laboratories report that levels of 30.0 to 74.0 nanograms per milliliter (ng/mL) are normal, humans well exposed to ultraviolet light have levels up to 88 ng/ml, suggesting that higher levels are optimal.
  • | Reference Library | WholeHealthMD 28 January 2010 2:02 UTC www.wholehealthmd.com [Source type: Academic]

[56][57][58][59]

Deficiency

.Low blood calcidiol (25-hydroxy-vitamin D) can result from avoiding the sun although deficiency may also exist in those with abundant exposure to bright sunlight.^ I may very well be Vitamin D deficient.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ Sun exposure cancer warnings ‘lead to Vitamin D deficiencies’ .

^ UV-B, the only band of light producing vitamin D, is significantly present only midday during summer months in most of the U.S. , the exact time we are advised to avoid sunlight.

[60] .Dietary intake supplies a modest amount of vitamin D as few foods contain a significant quantity of vitamin D relative to synthesis in the skin which can supply a large amount Some genetic diseases have the appearance of rickets,[61][62][63] these are associated with consanguineous marriage.^ Dietary Reference Intakes for vitamin D and calcium .
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

^ Foods containing the vitamin .
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Dietary Reference Intakes for vitamin D and calcium.

[64][65][66]>[67][68][69][70] and possibly .founder effect[71], Skin colour has also been associated with low 25(OH)D, especially in Africans living in countries with a temperate climate.^ The pharmacologic effects of 1,25-(OH) 2 D are profound and have resulted in the development of vitamin D analogues, that are approved for use in hyper-proliferative conditions such as psoriasis ( 12 ).
  • Chapter 8. Vitamin D 28 January 2010 2:02 UTC www.fao.org [Source type: Academic]

^ I, myself, have been diagnosed with very low bone density and, at the time of diagnosis, my Vitamin D (25-OH) was 10 nanograms per ml.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ The latter is often normal in the blood even when the precursor 25(OH)D is low or deficient.

.For example 25-OHD under 10ng/mL (25 nmol/l) in 44% of asymptomatic East African children living in Melbourne[72][73] However a study of healthy young Ethiopians living in Addis Ababa (10 degrees N) found average 25(OH)D levels of 23.5nmol/L.[74] A review of Vitamin D in Africa[75] gives the median levels for equatorial countries: Kenya 65.5 nmol/L and Zaire 65nmol/L, concluding that it remains to be established if associations between vitamin D status and health outcomes identified in Western countries can be replicated in African countries.^ It is the optimum level of 25(OH)D that is most strongly associated with general good health.

^ However, the relevance of these associations to cardiovascular morbidity remains to be established.

^ Levels of 1,25(OH) 2 D do not typically decrease until vitamin D deficiency is severe [ 5 , 10 ].
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

.Vitamin D levels are approximately 30% higher in northern Europe than in central and southern Europe, higher vitamin D concentrations in northern countries may have a genetic basis.^ But in fact their vitamin D levels were "markedly higher" than average.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ My vitamin D level is less than 4.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ Doses five times higher than this were consumed by a few individuals due to a manufacturing error; the resulting toxicity was severe and may have caused death in one individual.
  • Vitamin D 28 January 2010 2:02 UTC healthlibrary.epnet.com [Source type: Academic]
  • Vitamin D | ThirdAge Articles 28 January 2010 2:02 UTC www.thirdage.com [Source type: Academic]
  • Disease, Condition, & Injury Fact Sheets | NYU Langone Medical Center 28 January 2010 2:02 UTC www.med.nyu.edu [Source type: Academic]

[76][77] .In a meta-analysis of cross-sectional studies on serum 25(OH)D concentrations globally the levels averaged 54 nmol/l and were higher in women than men, and higher in Caucasians than in non-Caucasians.^ But in fact their vitamin D levels were "markedly higher" than average.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Serum concentration of 25(OH)D is the best indicator of vitamin D status.
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

^ Overall, women with BV had lower serum 25(OH)D concentrations than those without BV (P < 0.01).

.There was no trend in serum 25(OH)D level with latitude.^ There are no harmful levels of contaminants.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Effect of chronic anticonvulsant therapy on serum 25-hydroxycalciferol levels in adults.
  • Vitamin D 28 January 2010 2:02 UTC healthlibrary.epnet.com [Source type: Academic]
  • Vitamin D | ThirdAge Articles 28 January 2010 2:02 UTC www.thirdage.com [Source type: Academic]
  • Disease, Condition, & Injury Fact Sheets | NYU Langone Medical Center 28 January 2010 2:02 UTC www.med.nyu.edu [Source type: Academic]

^ "Serum 25-hydroxyvitamin D levels and risk of multiple sclerosis".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

[78] .African Americans often have a very low circulating 25(OH)D level, however those of African descent have higher parathyroid hormone and 1,25-Dihydroxycholecalciferol associated with lower 25-hydroxyvitamin D than other ethnic groups, moreover they have the greatest bone density[79] and lowest risk of fragility fractures compared to other populations.^ "Serum 25-hydroxyvitamin D levels and risk of multiple sclerosis".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ "Depression is associated with decreased 25-hydroxyvitamin D and increased parathyroid hormone levels in older adults".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ In institutionalized subjects 25(OH)D levels are often in the deficiency range.

[80][81][82] .African American adults are less likely to be diagnosed with coronary heart disease,[83] in 2006, 9.4% of white men, 7.8% of black men, and 5.3% of Mexican American men had coronary heart disease,[84] the NHANES I Epidemiologic Follow-up Study concluded African-American men aged 25 to 74 years had lower age-adjusted rates of coronary heart disease and acute myocardial infarction than white men of the same ages,[85] African Americans have a lower prevalence and extent of coronary artery calcium (CAC) than whites.^ D and risk of myocardial infarction in men: a prospective study".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Serum calcium: a new, independent prospective risk factor for myocardial infarction in middle-aged men followed for 18 years.
  • Vitamin D - Netrition.com 2 February 2010 18:56 UTC www.netrition.com [Source type: Academic]

^ Subsequent to this report, another investigator [ 44 ] evaluated vitamin D levels measured in NHANES 2001-2004 compared to NHANES III and reported a marked decline, leading some to suggest that the majority of children and adults in the United States (and almost all African Americans and Mexican Americans) are vitamin D insufficient.
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

[86] .The incidence of testicular cancer among African Americans was calculated to be one quarter of that among whites.^ Hypovitaminosis D prevalence and determinants among African-American and white women of reproductive age: third National Health and Nutrition Examination Survey, 1988-1994.
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

^ Hypovitaminosis D prevalence and determinants among African American and white women of reproductive age: Third National Health and Nutrition Examination Survey, 1988-1994.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ Studies found there are disparities in incidence and mortality of cancer between African-Americans and Caucasians and news media has attributed the disparities to the poor healthcare or treatments blacks receive.

[87] .Frank deficiency of vitamin D can result from a number of hereditary disorders.^ Over the last 5 years, I have tested almost every patient in my practice for vitamin D deficiency, and I have been shocked by the results.
  • Vitamin D -- Why You Are Probably NOT Getting Enough 28 January 2010 2:02 UTC www.ultrawellness.com [Source type: General]

^ NOT! I'm on treatment for vitamin D deficiency, loss of sleep, and seasonal affective disorder now.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ Once foods were fortified with vitamin D and rickets appeared to have been conquered, many health care professionals thought the major health problems resulting from vitamin D deficiency had been resolved.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

[3] Deficiency results in impaired bone mineralization, and leads to bone softening diseases[88] including:
.
  • Rickets, a childhood disease characterized by impeded growth, and deformity, of the long bones which can be caused by calcium or phosphorus deficiency as well as a lack of vitamin D, today it is largely found in low income counties in Africa, Asia or the Middle East.^ The two diseases traditionally associated with severe vitamin D deficiency—rickets in children and osteomalacia in adults—are characterized by deformation or softening of bone.

    ^ Vitamin D also assists in the retention of calcium and phosphorus.
    • Vitamin-D supplement 400 iu tablets, fat solube prohormone 2 February 2010 18:56 UTC www.physicianformulas.com [Source type: Academic]

    ^ Vitamin D deficiency does not cause rickets.
    • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
    • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

    [89][90][91] .Rickets was first described in the 17th century by Francis Glisson who stated in 1650 that it had first appeared about 30 years previously in the counties of Dorset and Somerset.^ Rickets was first described in the mid-17th century by British researchers [ 34 , 48 ].
    • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

    ^ But according to Michael F. Holick, director of the Vitamin D, Skin, and Bone Research Laboratory at Boston University Medical Center, who has spent 30 years studying the vitamin, “rickets can be considered the tip of the vitamin D–deficiency iceberg.” .

    ^ I am a 20-year breast cancer surivor, from a long list of close-degree relatives who did not survive the disease, so I am very passionate about this cause.
    • Vitamin D -- Why You Are Probably NOT Getting Enough 28 January 2010 2:02 UTC www.ultrawellness.com [Source type: General]

    [92] In 1857 John Snow (physician) suggested the rickets then widespread in Britain was being caused by the adulteration of bakers bread with alum.[93] .The role of diet in the development of rickets[94][95] was determined by Edward Mellanby between 1918–1920.[96] By altering the diets of dogs raised in the absence of sunlight, he was able to establish unequivocally that rickets was linked with diet, and identified cod liver oil as an excellent anti-rachitic agent and phytic acid as a rachitic agent.^ Cod liver oil, 1 tablespoon .
    • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

    ^ Fish liver oils, such as cod liver oil.
    • Vitamin D -- Why You Are Probably NOT Getting Enough 28 January 2010 2:02 UTC www.ultrawellness.com [Source type: General]

    ^ Cod-Liver-Oil pills .
    • Vitamin-D supplement 400 iu tablets, fat solube prohormone 2 February 2010 18:56 UTC www.physicianformulas.com [Source type: Academic]

    [97][98][99] .Nutritional rickets exists in countries with intense year round sunlight such as Nigeria and can occur without vitamin D deficiency.^ A greater prevalence of vitamin D deficiency exists in Middle Eastern countries.
    • Vitamin D Deficiency and Related Disorders: eMedicine Endocrinology 28 January 2010 2:02 UTC emedicine.medscape.com [Source type: Academic]

    ^ Vitamin D deficiency does not cause rickets.
    • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
    • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

    ^ Vitamin D deficiency is the most common cause of nutritional rickets.
    • Vitamin D Deficiency and Related Disorders: eMedicine Endocrinology 28 January 2010 2:02 UTC emedicine.medscape.com [Source type: Academic]

    .[100][101] In 1921 Elmer McCollum identified a substance found in certain fats that could prevent rickets.^ He began experimenting with city children and found that he could cure their rickets with exposure to sunshine alone.

    ^ Mar;16(3):422-9 - "We found strong evidence to support the hypothesis that vitamin D could help prevent breast cancer.

    ^ Vitamin D is also found in certain foods and is fat soluble.
    • Vitamin D | LIVESTRONG.COM 28 January 2010 2:02 UTC www.livestrong.com [Source type: FILTERED WITH BAYES]

    .Prior to the fortification of milk products with vitamin D, rickets was a major public health problem, in Denver where ultraviolet rays are approximately 20% stronger than at sea level on the same latitude[102] almost two thirds of 500 children had mild rickets in the late 1920's.^ In the 1930s, a milk fortification program was implemented in the United States to combat rickets, then a major public health problem.
    • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

    ^ My vitamin D level is less than 4.
    • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

    ^ Today it is rare to see a child with rickets in industrialized countries because milk is fortified with vitamin D. Moreover, most children get enough exposure to sunlight for their bodies to manufacture all the vitamin D that they need.
    • | Reference Library | WholeHealthMD 28 January 2010 2:02 UTC www.wholehealthmd.com [Source type: Academic]

    [103] .An increase in the amount of animal protein[104] in the 20th century American diet coupled with consumption of milk[105][106] fortified with relatively small quantities of vitamin D led to a dramatic decline in the number of rickets cases.^ Fortified foods provide most of the vitamin D in the American diet [ 4 , 26 ].
    • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

    ^ Small amounts of vitamin D may be necessary to increase absorption of calcium.

    ^ Fortified foods provide most of the vitamin D in the American diet [4,26].

    [42] .Although rickets is now rare in Britain there have been outbreaks in some immigrant communities but[107] the sufferers did not conform to the stereotype of concealing clothing.^ More recently, it has also been added to flour to reduce rickets among immigrants to Britain .

    ^ There is some consideration now being given that 1000 IU should be the new RDA (not that RDAs represent optimal levels).
    • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

    .Having darker skin and reduced exposure to sunshine did not produce rickets unless the diet deviated from a Western omnivore pattern characterized by high intakes of meat, fish and eggs, and low intakes of high-extraction cereals.^ It can also be produced in the skin during sun exposure.

    ^ Often we are advised to consume the egg white while the D is in the yolk or we eat the flesh of the fish avoiding the D containing skin, organs and fat.

    ^ Unless a person has an unusual medical condition or diet where blood vitamin D levels are suspected to be too low or too high, blood testing does not give us much of a clue of how much exactly to supplement.
    • Vitamin-D supplement 400 iu tablets, fat solube prohormone 2 February 2010 18:56 UTC www.physicianformulas.com [Source type: Academic]

    [108] .The dietry risk factors for rickets are independent of the low vitamin D content of most foods and appear to result from interactions between constituents of animal foods and the intermediary metabolism of endogenously-synthesized vitamin D.[109]
  • Osteomalacia, a bone-thinning disorder that occurs exclusively in adults and is characterized by proximal muscle weakness and bone fragility.^ Osteoporosis; and Osteomalacia: a bone-thinning disorder in adults that is characterized by proximal muscle weakness and bone fragility.
    • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

    ^ This risk appears to be low, but results indicate that megadoses should be avoided.
    • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

    ^ Vitamin D sufficiency prevents rickets in children and osteomalacia in adults [2,6,7].

    .The effects of osteomalacia are thought to contribute to chronic musculoskeletal pain.^ Deficiency has also possibly been found to be a source of chronic, non-specific musculoskeletal pain (2003 in the Mayo Clinic Proceedings).

    ^ Unlike osteoporosis, which is a painless disease, osteomalacia causes aching bone pain that is often misdiagnosed as fibromyalgia or chronic pain syndrome or is simply dismissed as depression.

    [110] .A number of reports thus indicate that vitamin D deficiency may be related to various types of pain,[111] but of the five small double-blind randomized controlled trials, only one found a reduction in pain after supplementation, and there is no persuasive evidence of lower vitamin D status in chronic pain sufferers compared to controls.^ Holick MF. Vitamin D deficiency: what a pain it is.
    • Vitamin D Deficiency and Related Disorders: eMedicine Endocrinology 28 January 2010 2:02 UTC emedicine.medscape.com [Source type: Academic]

    ^ Only this time they found that I had NO vitamin D in my system.
    • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

    ^ There is no evidence of toxicity with this vitamin.
    • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

    [112]
.There is an association between low 25(OH)D levels and an increased susceptibility to several chronic diseases, such as high blood pressure, tuberculosis, cancer, periodontal disease, multiple sclerosis, osteoporosis, chronic pain, seasonal affective disorder,[113][114] peripheral artery disease[115], cognitive impairment which includes memory loss and foggy brain,[116] and several autoimmune diseases including type 1 diabetes (see role in immunomodulation).^ "Serum 25-hydroxyvitamin D levels and risk of multiple sclerosis".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Epidemiological study finds a strong association between high 1,25 D levels and osteoporosis.
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

^ It helps protect against cancer and is also thought to be important in helping to prevent bone disease such as osteoporosis, as well as autoimmune diseases, asthma, diabetes, high blood pressure, depression, Parkinson’s disease and Multiple Sclerosis.

[9][42] .There is also an association between low vitamin D levels and parkinson's disease,[117] however such associations were found in observational studies and are not conclusive evidence of a causal link, (see correlation does not imply causation), a systemic review[118] found no significant effect of vitamin D supplements.^ Only this time they found that I had NO vitamin D in my system.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ There is no evidence of toxicity with this vitamin.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Effects of vitamin D supplementation in pregnancy.

.One leading[119] proponent of the view that the optimal concentration of 25(OH)D is at least 30 ng/ml [120] defines vitamin D deficiency as a 25(OH)D level of under 20 ng/ml (50 nmol/l), applying this criterion he regards 30% to 50% of the United States population as suffering from vitamin D deficiency.^ One can therefore be 25 (OH)D deficient and have normal serum calcitriol levels.
  • PaNu - PāNu Blog - Vitamin D 28 January 2010 2:02 UTC www.paleonu.com [Source type: General]

^ Vitamin D deficiency has been observed among many populations in the northern United States.

^ A level between 25 and 50 nmol/L is considered insufficient but not yet low enough to lead to a deficiency.

[121] .This includes areas with abundant sun exposure, such as Hawaii and southern Arizona where over 50% of inhabitants have 25(OH)D level of under 20 ng/ml.^ I, myself, have been diagnosed with very low bone density and, at the time of diagnosis, my Vitamin D (25-OH) was 10 nanograms per ml.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Radioimmunoassays measure total 25-hydroxyvitamin D, which includes levels of both 25-hydroxyvitamin D 2 and 25-hydroxyvitamin D 3 .
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ IU a day, monitor blood levels periodically and take higher doses under medical supervision if blood levels are below 50ng/ml .
  • | Reference Library | WholeHealthMD 28 January 2010 2:02 UTC www.wholehealthmd.com [Source type: Academic]

[122][123] .Such metrics[124] depart from more typical definitions of vitamin deficiency which are based on prevention of overt deficiency symptoms or comparable biologic indicators.^ [Prevention of vitamin D deficiency in adolescents and pre-adolescents.

^ There is no underlying cause except for vitamin D deficiency and an escalation from that into poorer and poorer health symptoms.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ When the use of baby formula became popular, enough vitamin D was added to the formula to prevent deficiency.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

[125][126]

Overdose by ingestion

.In healthy adults, sustained intake of 1250 micrograms/day (50,000 IU) can produce overt toxicity within months,[127] those with certain medical conditions are far more sensitive to vitamin D and devolop hypercalcaemia in response to any increase in vitamin D nutrition while maternal hypercalcaemia during pregnancy may increase foetal sensitivity to effects of vitamin D and lead to a syndrome of mental retardation and facial deformities.^ Vitamin D-3 2,000 IU, 120 Softgels .
  • Vitamin D Supplements at the Lowest Prices! 2 February 2010 18:56 UTC www.a1supplements.com [Source type: General]

^ Toxic effects have occurred in adults receiving 2,500 g (100,000 IU)/day for several months."

^ He talks about lifeguards producing 10,000 IU of vitamin D per day.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

[128][129] .If you have a medical condition, are pregnant or think you may be, or are breastfeeding, you must consult your doctor before taking a vitamin D supplement.^ Vitamin D supplement ORALLY is BAD for you.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ This information is not medical advice, if you are pregnant, nursing, taking medication, or have a medical condition, consult your physician.
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Did you take a Vitamin D supplement, and if so, has it helped?
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

.For infants (birth to 12 months) the tolerable Upper Limit, (maximum amount that can be tolerated without harm) is set at 25 micrograms/day (1000 IU).^ The maximum tolerated dose after the age of 12 months is 2,000 IU/day (50 mcg/day).
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Infants 0-12 months, 200 IU (5 micrograms) .

^ Birth to 12 months .
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

.1000 micrograms/day (40,000 IU) in infants has produced toxicity within 1 month.^ Also, some hypersensitive infants have developed toxicity symptoms at 1,000 IU per day.

^ The Merck Manual's assessment is somewhat different: "Vitamin D 1000 g (40,000 IU)/day produces toxicity within 1 to 4 months in infants, and as little as 75 g (3,000 IU)/day can produce toxicity over years.

^ Infants 0-12 months, 200 IU (5 micrograms) .

.Serum levels of calcidiol (25-hydroxy-vitamin D) are typically used to diagnose vitamin D overdose, these levels may be as much as 15-fold greater in cases of vitamin D toxicity.^ Vitamin D toxicity: How much is too Much?
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ These findings suggest a potential vasculoprotective role of vitamin D" Inverse association between serum 25(OH) vitamin D levels and non-melanoma skin cancer in elderly men - Cancer Causes Control.

^ As a result, the level of calciferol (25-D) may be reduced because it is being rapidly converted into calcitriol (1,25-D).
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

[3] .The U.S. Dietary Reference Intake Tolerable Upper Intake Level (upper limit) of vitamin D for children and adults is set at 50 micrograms/day (2,000 IU).^ Vitamin D-3 2,000 IU, 120 Softgels .
  • Vitamin D Supplements at the Lowest Prices! 2 February 2010 18:56 UTC www.a1supplements.com [Source type: General]

^ The safe upper limit of vitamin D consumption is 10,000 IU per day ...

^ A safe upper limit is 2,000 IU daily.

.Serum levels of calcidiol (25-hydroxy-vitamin D) are typically used to diagnose vitamin D overdose, these levels may be as much as 15-fold greater in cases of vitamin D toxicity.^ Vitamin D toxicity: How much is too Much?
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ These findings suggest a potential vasculoprotective role of vitamin D" Inverse association between serum 25(OH) vitamin D levels and non-melanoma skin cancer in elderly men - Cancer Causes Control.

^ As a result, the level of calciferol (25-D) may be reduced because it is being rapidly converted into calcitriol (1,25-D).
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

.Some symptoms of vitamin D toxicity are a result of hypercalcemia (an elevated level of calcium in the blood) caused by increased intestinal calcium absorption.^ The major function of vitamin D is to increase the efficiency of calcium absorption from the small intestine.
  • Vitamin D Deficiency and Related Disorders: eMedicine Endocrinology 28 January 2010 2:02 UTC emedicine.medscape.com [Source type: Academic]

^ Vitamin D controls the levels of calcium in the blood.

^ Vitamin D intake increases both calcium and phosphorus absorption.

.Vitamin D toxicity is known to be a cause of high blood pressure.^ Condition: High blood pressure Grade: C .
  • Vitamin D | LIVESTRONG.COM 28 January 2010 2:02 UTC www.livestrong.com [Source type: FILTERED WITH BAYES]

^ Vitamin D is very toxic in high doses.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Osteoporosis is not caused by low Vitamin D, it is caused by a weakness in the bone matrix due to a number of factors, Estrogen being high in importance.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

[130] .Gastrointestinal symptoms of vitamin D toxicity can include anorexia, nausea, and vomiting.^ Vitamin D toxicity can cause nonspecific symptoms such as nausea, vomiting, poor appetite, constipation, weakness, and weight loss [ 88 ].
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

^ Vitamin D taken in high amounts can cause excessive calcification of bone, calcification of soft tissue, kidney stones, headaches, weakness, nausea, and vomiting.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]
  • Vitamin-D supplement 400 iu tablets, fat solube prohormone 2 February 2010 18:56 UTC www.physicianformulas.com [Source type: Academic]

^ Symptoms of overdose include dizziness, nausea, vomiting, headache, skin damage, mental disturbances, and, in women, infrequent periods.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

.These symptoms are often followed by polyuria (excessive production of urine), polydipsia (increased thirst), weakness, nervousness, pruritus (itch), and eventually renal failure.^ Merck says, "The first symptoms are anorexia, nausea, and vomiting, followed by polyuria , polydipsia , weakness, nervousness, and pruritus .

^ Less common symptoms include diarrhea, increased thirst, increased urination, irritability, failure to gain weight in children.

^ Children taking 10,000 IU per day for 4 months can develop the following toxicity symptoms : headaches, weakness, nausea and vomiting, constipation, polyuria, polydipsia, diarrhea, and calcification of soft tissues such as kidneys, lungs, tympanic membrane or ears.

.Other signals of kidney disease including elevated protein levels in the urine, urinary casts, and a build up of wastes in the blood stream can also develop.^ There could be a normal level of the vitamin or medication in the blood stream yet untoward effects could be going on in some part of the body.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ People with higher blood levels of vitamin D may be less likely to develop gum disease.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Living at higher latitudes also increase the risk of having hypertension, type I diabetes, multiple sclerosis and other autoimmune diseases, and infectious diseases including tuberculosis and influenza.

[3] .In one study, hypercalciuria and bone loss occurred in four patients with documented vitamin D toxicity.^ Studies show calcium is only one of the important elements for healthy bones.

^ Based on the study, at least one rheumatologist is now administering megadoses of Vitamin D to a Lyme-RA patient.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

^ This study followed RA patients and the majority lost bone near their wrist joint over 2 years.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

[131] .Another study showed elevated risk of ischemic heart disease when serum 25-hydroxyvitamin D was above 89 ng/mL.[132] Vitamin D toxicity is treated by discontinuing vitamin D supplementation, and restricting calcium intake.^ "Serum 25-hydroxyvitamin D levels and risk of multiple sclerosis".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ "Intake of vitamin D and risk of type 1 diabetes: a birth-cohort study".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Dietary Reference Intakes for vitamin D and calcium .
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

.If the toxicity is severe blood calcium levels can be further reduced with corticosteroids or bisphosphonates.^ Vitamin D controls the levels of calcium in the blood.

^ Further reducing the risk of osteoporosis in African Americans are their lower levels of bone-turnover markers, shorter hip-axis length, and superior renal calcium conservation.
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]
  • Vitamin D 28 January 2010 2:02 UTC www.hoptechno.com [Source type: Academic]

^ Vitamin D maintains normal blood levels of calcium and phosphorus and promotes calcium absorption from the intestine.

Kidney damage may be irreversible.
.Exposure to sunlight for extended periods of time does not normally cause vitamin D toxicity.^ Vitamin D deficiency does not cause rickets.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]

^ Of note, prolonged exposure to the sun does not cause vitamin D toxicity.
  • Vitamin D Deficiency and Related Disorders: eMedicine Endocrinology 28 January 2010 2:02 UTC emedicine.medscape.com [Source type: Academic]

^ We recommend that enough vitamin D be taken daily to maintain 25-hydroxy vitamin D levels at levels normally achieved through summertime sun exposure (50 ng/ml).

[133] .This is because within about 20 minutes of ultraviolet exposure in light skinned individuals (3–6 times longer for pigmented skin) the concentration of vitamin D precursors produced in the skin reach an equilibrium, and any further vitamin D that is produced is degraded.^ Vitamin D3 is produced in the skin during exposure to sunlight.

^ However, if longer exposure times are had, even with the darkest skin color, sufficient levels of vitamin D are produced.

^ It can also be produced in the skin during sun exposure.

[17] .According to some sources, endogenous production with full body exposure to sunlight is approximately 250 µg (10,000 IU) per day.^ He talks about lifeguards producing 10,000 IU of vitamin D per day.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ I am taking 10,000 IU per day until I get into the optimal range.
  • Vitamin D -- Why You Are Probably NOT Getting Enough 28 January 2010 2:02 UTC www.ultrawellness.com [Source type: General]

^ The safe upper limit of vitamin D consumption is 10,000 IU per day ...

[133] According to Holick, "the skin has a large capacity to produce cholecalciferol"; his experiments indicate that,
"[W]hole-body exposure to one minimal erythemal dose of simulated solar ultraviolet radiation is comparable with taking an oral dose of between 250 and 625 micrograms (10 000 and 25 000 IU) vitamin D."[17]
.It is on the basis of the supposedly similar effect of supplementation and whole body exposure to one erythemal dose that a leading researcher [134] has suggested that 250 micrograms/day (10,000 IU) in healthy adults should be adopted as the tolerable upper limit.^ Posted by effects of adult supplement drinks on in .
  • Brazil - the week end (Girodelmondo en) 11 September 2009 3:03 UTC www.robertobaggio.com [Source type: General]

^ The safe upper limit of vitamin D consumption is 10,000 IU per day ...

^ Tolerable upper limit is 2000 mg/day in adults (the limit is lower in children).
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

[134] .Supplements and skin synthesis have a different effect on on serum 25(OH)D concentrations;[135] endogenously synthesized vitamin D3 travels in plasma almost exclusively on vitamin D-binding protein (VDBP), providing for a slower hepatic delivery of the vitamin D and the more sustained increase in plasma 25-hydroxycholecalciferol observed after depot, parenteral administration of vitamin D. Yet the orally administered route vitamin D produces swift hepatic delivery of vitamin D, and transient, but nonetheless abrupt, increases in plasma 25-hydroxycholecalciferol.^ Vitamin D3 is produced in the skin during exposure to sunlight.

^ Vitamin D supplement ORALLY is BAD for you.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ "Aging decreases the capacity of human skin to produce vitamin D3".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

.The richest food source of vitamin D - wild salmon - would require 35 ounces a day to provide 10,000IU.[136] It has been argued[137] that ingestion of vitamin D in large amounts was achieved in the process of grooming by furry human ancestors and that from UV-exposed human skin secretions early humans ingested vitamin D by licking the skin, however this putative ingestion of vitamin D by early humans is not quantified.^ Q. Are there food sources of vitamin D? .

^ A human requires ten to fifteen minutes of sun exposure at least twice a week on the face, arms, hands, or back without sunscreen with a greater than 3 UV index for adequate amounts of vitamin D 3 .
  • What Is Vitamin D? What Are The Benefits Of Vitamin D? 2 February 2010 18:56 UTC www.medicalnewstoday.com [Source type: Academic]

^ Vitamin D3 is produced in skin exposed to sunlight, specifically ultraviolet B radiation.
  • Vitamin D Supplements at the Lowest Prices! 2 February 2010 18:56 UTC www.a1supplements.com [Source type: General]

.A study[138] found 34% of its sample of healthy western Canadians to be be under 40nmol/L at some point and 97% to be under 80nmol/L at least once.^ I found a place that was doing some studies on PTH and Vit.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ Some studies have found it will take about two months for the body to become deficient.

^ The study found that 10% had at least one advanced cancerous lesion.
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]
  • Vitamin D 28 January 2010 2:02 UTC www.hoptechno.com [Source type: Academic]

It has been questioned.[139] whether to ascribe a state of sub-optimal vitamin .D status when the variation in seasonal fluctuations in vitamin D will naturally produce a period of falling levels, and such a seasonal decline has been a part of Europeans' adaptive environment[140] for 1000 generations,[141] is clear thinking.^ Since dietary vitamin D is found naturally only in a few foods, such as cod liver oil, dietary intake would not be sufficient for most people.

^ Excessive levels of vitamin D intake over an extended period can lead to headaches, kidney stones, and weight loss.

^ Same with vitamin D. It is possible that blood levels could be low or normal, yet untoward reactions could be occurring in other tissues, such as brain tissue.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

.Still more contentious is recommending supplementation when those supposedly in need of it are labeled healthy and serious doubts exist as to the long term effect of attaining and maintaining serum 25(OH)D of at least 80nmol/L by supplementation.^ Long-term supplementation, without monitoring, may have serious consequences.

^ Except in those with conditions causing hypersensitivity, there is no evidence of adverse effects with serum 25(OH)D concentrations <140 nmol /L, which require a total vitamin D supply of 250 microg (10,000 IU)/d to attain.

^ Need AG, Morris HA, Horowitz M, Nordin C. Effects of skin thickness, age, body fat, and sunlight on serum 25-hydroxyvitamin D. Am J Clin Nutr 1993;58:882-5.

[142] .Possible ethnic differences in physiological pathways for ingested vitamin D, such as Inuit have, may confound across the board recommendations for vitamin D levels.^ It’s possible that mothers’ vitamin D levels late in pregnancy have lasting effects on their children’s later bone development, the researchers report in the Journal of Clinical Endocrinology and Metabolism.

^ Same with vitamin D. It is possible that blood levels could be low or normal, yet untoward reactions could be occurring in other tissues, such as brain tissue.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Although vitamin D supplements above recommended levels given in clinical trials have not shown harm, most trials were not adequately designed to assess harm [5].

.Inuit compensate for lower production of vitamin D by converting more of this vitamin to its most active form [143] Another study by the Toronto group[144] did have 'young Canadian adults of diverse ancestry ' but applied a standard of serum 25(OH)D levels that was significantly higher than official recommedations.^ But in fact their vitamin D levels were "markedly higher" than average.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Vitamin D and older adults: More than just a bone problem?.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ The precursor is a better marker of vitamin-D status (or reserves) than the most active 1,25(OH)D form.

[145][146], .75 nmol/L as "optimal", between 75 nmol/L and 50 nmol/L as "insufficient" and < 50 nmol/L as "deficient" [37].^ A level between 25 and 50 nmol/L is considered insufficient but not yet low enough to lead to a deficiency.

^ An appropriate lower normal limit may be between 50-100 nmol/l (20-40 ng/ml).

^ I am 29 years old and was recently diagnosed with vitamin D Deficiency 14 nmol/L. (normal range is 75-250nmol/L).
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

.In our study, we report the percentage of the individuals in our sample under three widely used cutoffs, 25 nmol/L, 50 nmol/L and 75 nmol/L, and we consider 25(OH)D levels > 75 nmol/L as optimal'. The results were ' 22% of individuals of European ancestry had 25(OH)D levels less than the 40 nmol/L cutoff, which is comparable to the values observed in previous studies [28,38].^ Anything above 75 nanomoles per litre (nmol/L) of 25-OHD is considered optimal.

^ My vitamin D level is less than 4.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ Optimal values of 25(OH)D are 40-50 ng/ml Acceptable values of 25(OH)D are 35-55 ng/ml Levels above 55 ng/ml will be toxic for some individuals.

.However, in our study, 78% of individuals of East Asian ancestry and 77% of individuals of South Asian ancestry had 25(OH)D concentrations lower than 40 nmol/L.The East Asians in the Toronto sample had low 25(OH)D levels when compared to whites.^ I, myself, have been diagnosed with very low bone density and, at the time of diagnosis, my Vitamin D (25-OH) was 10 nanograms per ml.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ The prevalence of serum concentrations of 25(OH)D less than or equal to 15 ng/mL (less than or equal to 37.5 nmol/L) was 10 times greater for the African American women (42.2%) than for the white women (4.2%).

^ Today, desirable serum 25(OH)D levels of at least 75 nmol/l may only be reached in about one third of US older individuals and even fewer European older individuals" Vitamin D Deficiency Is Associated With Low Mood and Worse Cognitive Performance in Older Adults - Am J Geriatr Psychiatry.

Lipps (2010)[147] in a world wide review says 'vitamin D deficiency (serum 25(OH)D<25nmol/l) is highly prevalent in China, another study says "A survey in Beijing indicated that Vitamin D-deficiency (plasma 25(OH)D concentration <12.5 nmol/l) occurred in more than 40% of adolescent girls in winter." A 2007 study in China[148] found that "higher serum 25(OH)D concentrations were associated with significantly increased risk of squamous dysplasia. No obvious source of measured or unmeasured confounding explains this finding".
.In South Asians Harinarayan (2009[149] found "All studies uniformly point to low 25(OH)D levels in the populations studies despite abundant sunshine in our country". For example rural men around Delhi average 44nmol/L Studies from northern India showed vitamin D deficiency (< 20 ng/ml) in pregnant women and their new born.^ Hyperparathyroidism due to low vitamin D levels .

^ Levels of 1,25(OH) 2 D do not typically decrease until vitamin D deficiency is severe [ 5 , 10 ].
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

^ They found 94% of people in the study had a vitamin D (25-hydroxyvitamin D) deficiency or insufficiency.

.Interestingly one of the studies has showed pregnant women in winter had higher 25(OH)D levels than in summer.^ Epidemiological data show low levels of vitamin D lead to a higher incidence of breast cancer, colon cancer, prostate cancer, ovarian cancer, as well as multiple myeloma.
  • Vitamin-D supplement 400 iu tablets, fat solube prohormone 2 February 2010 18:56 UTC www.physicianformulas.com [Source type: Academic]

^ Studies show calcium is only one of the important elements for healthy bones.

^ No one is recommending that pregnant women bask in the sun.

Studies from south India, Tirupati also showed a similar trend. .Healthy Indians living at the latitude they are presumably best adapted to seem have low 25(OH)D levels which are not very different from healthy South Asians living in Canada.^ D level was very low.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ As many as half of older adults in the United States with hip fractures could have serum 25(OH)D levels <12 ng/mL ( <30 nmol/L) [ 5 ].
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

^ I was shocked when I was just told I have a very low level of vitamin D in my system.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

.South Indian patients with ischemic heart disease have serum 25-hydroxyvitamin D3 levels are extremely high -above 222.5 nmol/l[150] The Toronto group conclude -"skin pigmentation, assessed by measuring skin melanin content, showed an inverse relationship with serum 25(OH)D". The uniform occurence of very low serum 25(OH)D in Indians living in India and Chinese in China does not support the hypothesis that the low levels seen in the more pigmented are due to a lack of synthesis from the sun, the leader of the study has nonetheless urged dark-skinned immigrants to take vitamin D supplements; "I see no risk, no downside, there's only a potential benefit".[151][152] A study of French Canadians]] [153] found that D a significant minority did not maximize ingested serum 25(OH)D; vitamin D-binding protein (VDBP), polymorphisms explained as much of the variation in circulating 25(OH)D as did total ingestion of vitamin D.[154] varies with the season in young adults and in the elderly being lower during the winter in Southern Europe than in both North America and Scandinavia, oral vitamin D intake,[155] is lower in Europe than both North America and Scandinavia.^ Vitamin D from Sun or supplement pill?
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Radioimmunoassays measure total 25-hydroxyvitamin D, which includes levels of both 25-hydroxyvitamin D 2 and 25-hydroxyvitamin D 3 .
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ Clinical improvement was more evident in Group B patients (those taking vitamin D) as compared to Group A patients.

[156] .It has been suggested that a founder effect is responsible for pseudo-vitamin D-deficiency rickets among French Canadians[157], in Kashmir, India patients with pseudovitamin D deficiency rickets had grossly raised 25-hydroxyvitamin D concentrations.^ Inactivating mutations in the human 25-hydroxyvitamin D 3 1 -hydroxylase gene in patients with pseudovitamin D-deficiency rickets.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ Vitamin D deficiency does not cause rickets.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

^ Jul 25 - "Our results suggest that the inverse association between UV exposure and NHL risk may be mediated by the vitamin D pathway" A Nested Case-Control Study of Plasma 25-Hydroxyvitamin D Concentrations and Risk of Colorectal Cancer - J Natl Cancer Inst.

.[158] Whether the toxicity of oral intake of vitamin D is due to that route being unnatural as suggested by Fraser.^ The current Recommended Dietary Allowance (RDA) for vitamin D is being revised, and some experts suggest that adults should take at least 2000 IU of vitamin D daily.

^ Osteoporosis is not caused by low Vitamin D, it is caused by a weakness in the bone matrix due to a number of factors, Estrogen being high in importance.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

^ Even if such figures were not directly applicable to human beings, vitamin D must remain one of the most non-toxic substances imaginable.

[159][160] is not known, but there is a certain amount of evidence to suggest that dietary vitamin .D may be carried by lipoprotein particles into cells of the artery wall and atherosclerotic plaque, where it may be converted to active form by monocyte-macrophages.^ As a result, the level of calciferol (25-D) may be reduced because it is being rapidly converted into calcitriol (1,25-D).
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

^ As people age, skin cannot synthesize vitamin D as efficiently and the kidney is less able to convert vitamin D to its active hormone form [ 4 , 53 ].
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]

^ Vitamin D receptors and 1α-hydroxylase (1α-OHase), the enzyme responsible for converting Vitamin D into it's active form, are heavily expressed in the substantia nigra, the region of brain where dopaminergic neurons are located.
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

[161] .These findings raise questions regarding the effects of vitamin D intake on atherosclerotic calcification and cardiovascular risk.^ "Vitamin D deficiency and risk of cardiovascular disease".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ "Intake of vitamin D and risk of type 1 diabetes: a birth-cohort study".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Together, these studies provide robust evidence of the beneficial effects that calcium and vitamin D can have on cancer prevention.

.Dietary vitamin D may be causing vascular[162] calcification.^ Vitamin D and vascular calcification.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Vitamin K deficiency can cause anorexia, lethargy, growth retardation, bone loss, soft tissue calcification, and death.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ One study reported that the immune systems of elderly people may benefit from higher levels of vitamin E than the dietary recommended dosage.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

Health effects

Immunomodulation

.The hormonally active form of vitamin D mediates immunological effects by binding to nuclear vitamin D receptors (VDR) which are present in most immune cell types including both innate and adaptive immune cells.^ Vitamin D receptors are present on cells responsible for both the innate and adaptive immune response, including T cells, B cells, macrophages, and dendritic cells.
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Retinol is the most active form of vitamin A. .
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Vitamin can be considered both a vitamin and a hormone.

.The VDR is expressed constitutively in monocytes and in activated macrophages, dendritic cells, NK cells, T and B cells.^ Vitamin D receptors are present on cells responsible for both the innate and adaptive immune response, including T cells, B cells, macrophages, and dendritic cells.
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ It is also likely that the 1,25(OH) 2 D produced in monocytes or macrophages is released to act locally on activated T lymphocytes, which regulate cytokine synthesis, and activated B lymphocytes, which regulate immunoglobulin synthesis.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ VDRs are found on B and T lymphocytes and monocytes, all cells involved in immune function.
  • PaNu - PāNu Blog - Vitamin D 28 January 2010 2:02 UTC www.paleonu.com [Source type: General]

.In line with this observation, activation of the VDR has potent anti-proliferative, pro-differentiative, and immunomodulatory functions including both immune-enhancing and immunosuppressive effects.^ In addition to immune cells that may control cancer promotion, cells of tissues susceptible to cancer also express the VDR. Vitamin D binds to the VDR and new proteins are synthesized that control cell differentiation, proliferation and recognition of adjacent cells, all functions important in the development of cancer.
  • PaNu - PāNu Blog - Vitamin D 28 January 2010 2:02 UTC www.paleonu.com [Source type: General]

^ D3’s effect on immune function improves resistance to infection by strengthening the innate immune system, for instance by supporting phagocytosis and destruction of invading organisms.
  • PaNu - PāNu Blog - Vitamin D 28 January 2010 2:02 UTC www.paleonu.com [Source type: General]

^ Vitamin D receptors are present on cells responsible for both the innate and adaptive immune response, including T cells, B cells, macrophages, and dendritic cells.
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

[163]
.VDR ligands have been shown to increase the activity of natural killer cells, and enhance the phagocytic activity of macrophages.^ In addition, the release of insulin from beta islet cells depends on calcium [34] , which is also regulated by Vitamin D. Additionally, Vitamin D has been shown to increase glucose transport into the cell.
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ High-protein diets increase the activity of the mixed-function oxidase system and enhance the metabolism of numerous drugs.

[22] .Active vitamin D hormone also increases the production of cathelicidin, an antimicrobial peptide that is produced in macrophages triggered by bacteria, viruses, and fungi.^ "The way the bacteria stop the VDR from transcription is to produce ever-increasing concentrations of an antagonist, such as Capnine, which ultimately stop 1,25-D from activating the VDR. In this way the bacteria stop the VDR from tanscribing most of the antimicrobial peptides."
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

^ D3, the active form of vitamin D, was reclassified as a hormone that controlled calcium metabolism.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

^ Additionally, vitamin D deficiency causes an increase in parathyroid hormone, which increases insulin resistance and is associated with diabetes, hypertension, inflammation, and increased cardiovascular risk.

[164] .Vitamin D deficiency tends to increase the risk of infections, such as influenza[165] and tuberculosis[166][167][168].^ "Vitamin D deficiency and risk of cardiovascular disease".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Observational studies suggest that vitamin D deficiency increases risk of respiratory infections.

^ Increased incidence of respiratory infection is linked to Vitamin D deficiency.
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

.In a 1997 study, Ethiopian children with rickets were 13 times more likely to get pneumonia than children without rickets.^ Epidemiological studies indicate that people with low levels of Vitamin D are 40% more likely to have a respiratory infection.
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ In ducks, it is even higher: EPA's LD 50 for mallards is greater than 2000 mg/kg, more than three times that for female rats.

^ (Note: Do not take more than 1,000 IU of vitamin D without testing and supervision by a knowledgeable healthcare practitioner.

[169]
.Effects of VDR-ligands, such as vitamin D hormone, on T-cells include suppression of T cell activation and induction of regulatory T cells, as well as effects on cytokine secretion patterns.^ Experimental data also demonstrate that physiologic vitamin D actions include the inhibition of processes that are important for intimal and medial artery calcification such as pro-inflammatory cytokine release, adhesion molecule release, and proliferation and migration of vascular smooth muscle cells.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Not that many foods contain vitamin D. Some fish, such as salmon, tuna and mackerel, as well as fish liver oils are considered to be the best sources.
  • What Is Vitamin D? What Are The Benefits Of Vitamin D? 2 February 2010 18:56 UTC www.medicalnewstoday.com [Source type: Academic]

^ Ismail F, Corder CN, Epstein S, Barbi G, Thomas S. Effects of pravastatin and cholestyramine on circulating levels of parathyroid hormone and vitamin D metabolites.

[170] .VDR-ligands have also been shown to affect maturation, differentiation, and migration of dendritic cells, and inhibits DC-dependent T cell activation, resulting in an overall state of immunosuppression.^ VDR-ligands have also been shown to affect maturation, differentiation, and migration of dendritic cells, and inhibits DC-dependent T cell activation, resulting in an overall state of immunosuppression.

^ Effects of VDR- ligands , such as vitamin D hormone, on T-cells include suppression of T cell activation and induction of regulatory T cells , as well as effects on cytokine secretion patterns.

^ In addition, the release of insulin from beta islet cells depends on calcium [34] , which is also regulated by Vitamin D. Additionally, Vitamin D has been shown to increase glucose transport into the cell.
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

[171]
.These immunoregulatory properties indicate that ligands with the potential to activate the VDR, including supplementation with calcitriol (as well as a number of synthetic modulators), may have therapeutic clinical applications in the treatment of inflammatory diseases (rheumatoid arthritis, psoriatic arthritis), dermatological conditions (psoriasis, actinic keratosis), osteoporosis, cancers (prostate, colon, breast, myelodysplasia, leukemia, head and neck squamous cell carcinoma, and basal cell carcinoma), and autoimmune diseases (systemic lupus erythematosus, type I diabetes); central nervous systems diseases (multiple sclerosis); and in preventing organ transplant rejection.^ These include prevention of cancer and the autoimmune diseases, insulin-dependent diabetes and multiple sclerosis.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ D and an increased risk for Type 1 diabetes, multiple sclerosis, Crohn's disease, hypertension and cardiovascular disease ...

^ These include colon, breast, and prostate cancers.

[163]
.A 2006 study published in the Journal of the American Medical Association, reported evidence of a link between Vitamin D deficiency and the onset of multiple sclerosis; the authors posit that this is due to the immune-response suppression properties of Vitamin D.[172] Further research conducted in 2009 indicates that vitamin D is required to activate a histocompatibility gene (HLA-DRB1*1501) necessary for differentiating between self and foreign proteins in a subgroup of individuals genetically predisposed to MS.[173] Suggestions that pregnant women take vitamin D during their pregnancy, especially during winter months, is beginning to show merit to lessen the likelihood of the child developing MS later in life.^ Vitamin D supplementation during Antarctic winter.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ Depression treatment Vitamin D and depressive symptoms in women during the winter: a pilot study.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Several months of supplementation may be required to show positive results if the deficiency is severe and prolonged.

[174][175]

Cancer

.The vitamin D hormone, calcitriol, has been found to induce death of cancer cells in vitro and in vivo.^ The vitamin D hormone, calcitriol, has been found to induce death of cancer cells in vitro and in vivo .

^ Vitamin D deficiency has been associated with increased risk of common cancers, such as breast, colon, lung, prostate and pancreatic cancer cells.
  • Liquid Vitamin D3 | Vitamin D | StopAgingNow.com 2 February 2010 18:56 UTC www.stopagingnow.com [Source type: Academic]

^ The mechanism for vitamin D health-related benefits has been linked to the regulatory role of 25-hydroxyvitamin D on cellular growth both in normal and cancer cells 12 .
  • Vitamin D position statement. DermNet NZ 28 January 2010 2:02 UTC dermnetnz.org [Source type: Academic]

.The anti-cancer activity of vitamin D is thought to result from its role as a nuclear transcription factor that regulates cell growth, differentiation, apoptosis and a wide range of cellular mechanisms central to the development of cancer.^ In particular, calcitriol, an active form of vitamin D, has a critical role in regulating cellular mechanisms involved in cancer development.

^ The role of vitamin D in cancer prevention.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ "The role of vitamin D in prostate cancer".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

[176] .These effects may be mediated through vitamin D receptors expressed in cancer cells.^ Nov 21 - "Research strongly supports the view that efforts to improve vitamin D status would have significant protective effects against the development of cancer.

^ Together, these studies provide robust evidence of the beneficial effects that calcium and vitamin D can have on cancer prevention.

^ Estrogen and other steroid hormones pass through the cell membrane and bind to specific receptor proteins inside the cell.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

[22]
.In 2005, scientists released a metastudy which demonstrated a beneficial correlation between vitamin D intake and prevention of cancer.^ What's the right Vitamin D dose for cancer prevention?
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ The role of vitamin D in cancer prevention.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ Vitamin D and prevention of colorectal cancer.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

.Drawing from a meta-analysis of 63 published reports, the authors showed that intake of an additional 1,000 international units (IU) (or 25 micrograms) of vitamin D daily reduced an individual's colon cancer risk by 50%, and breast and ovarian cancer risks by 30%.^ The second, on ovarian cancer, was published Oct.

^ The Doctor put me on 50,000 IU's of vitamin D for 6 weeks.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ "Vitamin D and prevention of breast cancer: pooled analysis".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

[177][178][179] .A scientific review undertaken by the National Cancer Institute found that vitamin D was beneficial in preventing colorectal cancer, which showed an inverse relationship with blood levels of 80 nmol/L or higher associated with a 72% risk reduction.^ Vitamin D controls the levels of calcium in the blood.

^ What's the right Vitamin D dose for cancer prevention?
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Risk of colorectal cancer was inversely correlated with dietary vitamin D and calcium.

.However, the same study found no link between baseline vitamin D status and overall cancer mortality.^ Prospective study of predictors of vitamin D status and cancer incidence and mortality in men.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ "Prospective study of predictors of vitamin D status and cancer incidence and mortality in men".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ However, studies evaluating the population as a whole found that there was no difference in mortality rate between those who took vitamin supplements and those who didn't.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

[180]
.A 2006 study using data on over 4 million cancer patients from 13 different countries showed a marked difference in cancer risk between countries classified as sunny and countries classified as less–sunny for a number of different cancers.^ Epidemiological data show low levels of vitamin D lead to a higher incidence of breast cancer, colon cancer, prostate cancer, ovarian cancer, as well as multiple myeloma.
  • Vitamin-D supplement 400 iu tablets, fat solube prohormone 2 February 2010 18:56 UTC www.physicianformulas.com [Source type: Academic]

^ A review of dozens of studies, including several large long-term ones, on the relationship between vitamin D and certain types of cancer showed vitamin D has the ability to reduce the incidence of certain cancers.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ A preliminary look at the three-year data show a similar strong association between higher maternal vitamin D levels and lower risk of wheezing and asthma at age three years.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

[181] .Research has also suggested that cancer patients who have surgery or treatment in the summer — and therefore make more endogenous vitamin D — have a better chance of surviving their cancer than those who undergo treatment in the winter when they are exposed to less sunlight.^ Cancer patients with high levels of vitamin D more likely to survive .

^ Also, consider also taking more in the winter and less in the summer season.
  • Vitamin-D supplement 400 iu tablets, fat solube prohormone 2 February 2010 18:56 UTC www.physicianformulas.com [Source type: Academic]

^ More is needed in the winter season and less in the summer season.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

[182] .Another 2006 study found that taking the U.S. RDA of vitamin D (400 IU per day) cut the risk of pancreatic cancer by 43% in a sample of more than 120,000 people from two long-term health surveys.^ He talks about lifeguards producing 10,000 IU of vitamin D per day.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ The safe upper limit of vitamin D consumption is 10,000 IU per day ...

^ IU per day of vitamin D3 ...

[183][184] .A randomized intervention study involving 1,200 women, published in June 2007, reports that vitamin D supplementation (1,100 international units (IU)/day) resulted in a 60% reduction in cancer incidence, during a four-year clinical trial, rising to a 77% reduction for cancers diagnosed after the first year (and therefore excluding those cancers more likely to have originated prior to the vitamin D intervention).^ RESULTS: 320 women completed the study.

^ Vitamin D supplementation during Antarctic winter.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ IU per day of vitamin D3 ...

[185][186] .Research has also indicated beneficial effects of high levels of calcitriol on patients with advanced prostate cancer.^ Cancer patients with high levels of vitamin D more likely to survive .

^ Epidemiological data show low levels of vitamin D lead to a higher incidence of breast cancer, colon cancer, prostate cancer, ovarian cancer, as well as multiple myeloma.
  • Vitamin-D supplement 400 iu tablets, fat solube prohormone 2 February 2010 18:56 UTC www.physicianformulas.com [Source type: Academic]

^ Nov 21 - "Research strongly supports the view that efforts to improve vitamin D status would have significant protective effects against the development of cancer.

[187]
.Low levels of vitamin D in serum have also been correlated with breast cancer disease progression and bone metastases,[188] and studies suggest that increased intake of vitamin D reduces the risk of breast cancer in premenopausal women.^ "Intake of vitamin D and risk of type 1 diabetes: a birth-cohort study".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Hyperparathyroidism due to low vitamin D levels .

^ Several studies suggest that vitamin D supplementation in children reduces the risk of type 1 diabetes.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

[189] .Polymorphisms of the vitamin D receptor (VDR) gene have been associated with an increased risk of breast cancer.^ Vitamin D supplementation also reduces the risk of prostate cancer and [69] breast cancer.
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Associated with a higher risk for prostate cancer and breast cancer risk.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Diets low in vitamin A may also increase the risk of developing cancer.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

[188] .Impairment of the VDR-mediated gene expression is thought to alter mammary gland development or function and may predispose cells to malignant transformation.^ Vieth suggests that vitamin D inhibits a mechanism by which cancer cells spread or it may boost the function of blood vessels or the immune system.

^ Vitamin D Nuclear Receptor (VDR) influences the expression of over 1,000 genes, including those associated with diseases such as cancer and multiple sclerosis.

^ Puchacz E, Stumpf WE, Stachowiak EK, Stachowiak MK. Vitamin D increases expression of the tyrosine hydroxylase gene in adrenal medullary cells.

.Women with homozygous FOK1 mutations in the VDR gene had an increased risk of breast cancer compared with the women who did not.^ Lin and her Harvard colleagues focused on these nutrients’ effects on breast cancer by analyzing data from the Women’s Health Study, funded by the National Institutes of Health.

^ Sep 14 - "Daily vitamin D was more effective than weekly, and monthly administration was the least effective" Vitamin D intake and breast cancer risk in postmenopausal women: the Iowa Women's Health Study - Cancer Causes Control.

^ Children of women living in an inner city who had vitamin D deficiency during pregnancy are at increased risk for wheezing illnesses.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

.FOK1 mutation has also been associated with decreasing bone mineral density which in turn may be associated with an increase in the risk of breast cancer.^ Diets low in vitamin A may also increase the risk of developing cancer.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Obesity may also increase risk.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Increased risk of bone fractures.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

[190]
.The Canadian Cancer Society was the first to recommend, in 2007, that all of its adult citizens begin taking 1,000 IU per day of vitamin D. The country's northern latitude was a factor in the decision, as was the growing body of evidence showing the vitamin's effectiveness in lowering instances of cancer.^ He talks about lifeguards producing 10,000 IU of vitamin D per day.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ The safe upper limit of vitamin D consumption is 10,000 IU per day ...

^ IU per day of vitamin D3 ...

[191][192]

Cardiovascular disease

.There is a certain amount of evidence to suggest that dietary vitamin D may be carried by lipoprotein particles into cells of the artery wall and atherosclerotic plaque, where it may be converted to active form by monocyte-macrophages.^ There is no evidence of toxicity with this vitamin.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Retinol is the most active form of vitamin A. .
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ D disregulation going on which basically is the conversion of 25 OH vitamin D into its active form 1, 25 Dihydroxy Vitamin D. This conversion which is normally controlled by kidneys goes out of whack when L form and Cell Wall Deficient bacteria start converting outside of your kidneys and this plays havoc with your system.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

[193] .These findings raise questions regarding the effects of vitamin D intake on atherosclerotic calcification and cardiovascular risk.^ "Vitamin D deficiency and risk of cardiovascular disease".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ "Intake of vitamin D and risk of type 1 diabetes: a birth-cohort study".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Together, these studies provide robust evidence of the beneficial effects that calcium and vitamin D can have on cancer prevention.

.Dietary vitamin D may be causing vascular[194] calcification.^ Vitamin D and vascular calcification.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Vitamin K deficiency can cause anorexia, lethargy, growth retardation, bone loss, soft tissue calcification, and death.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Vitamin D2 also doesn’t last as long in our circulation and may even cause premature breakdown of circulating D3.

[195][196] .Vitamin D deficiency is associated with an increase in high blood pressure and cardiovascular risk.^ Children and young adults are also potentially at high risk for vitamin D deficiency.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ High blood pressure (hypertension) .

^ D deficiency has been associated with an increased risk for Type 1 diabetes .

.Numerous observational studies show this link, but no randomized trial has proven the impact of vitamin D supplementation.^ Most supplementation trials of the effects of vitamin D on bone health also include calcium, so it is not possible to isolate the effects of each nutrient.
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]
  • Vitamin D 28 January 2010 2:02 UTC www.hoptechno.com [Source type: Academic]

^ In patients with Th1 inflammation, the production, by sunlight, of 1,25-D in the skin predominates the production of 25-D. Studies show that all 25-D produced in the skin from sunlight is hydroxylated directly into 1,25-D, leaving no 25-D to be stored.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]

^ However, studies evaluating the population as a whole found that there was no difference in mortality rate between those who took vitamin supplements and those who didn't.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

[197] .The precise mechanism for cardiovascular regulation is still under investigation; possibilities include blood pressure regulation through the renin-angiotensin system, parathyroid hormone levels, direct impact on heart muscle function, inflammation, and vascular calcification.^ Additionally, vitamin D deficiency causes an increase in parathyroid hormone, which increases insulin resistance and is associated with diabetes, hypertension, inflammation, and increased cardiovascular risk.

^ They compared change in vitamin D levels with changes in knee pain, physical function and muscle strength during the 30-month study period.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ I have subsequently -- and under monitoring -- taken 4,000 I.U. of D3 and still only managed to raise my levels to 39.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

[198]
.When researchers monitored the vitamin D levels, blood pressure and other cardiovascular risk factors of 1739 people, of an average age of 59 years for 5 years, they found that those people with low levels of vitamin D had a 62% higher risk of a cardiovascular event than those with normal vitamin D levels.^ Vitamin D controls the levels of calcium in the blood.

^ But in fact their vitamin D levels were "markedly higher" than average.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ This suggests that factors other than vitamin D provide protection [68].

[199] .Low levels of vitamin D have also been implicated in hypertension, elevated VLDL triglycerides, and impaired insulin metabolism.^ Hyperparathyroidism due to low vitamin D levels .

^ Epidemiological data show low levels of vitamin D lead to a higher incidence of breast cancer, colon cancer, prostate cancer, ovarian cancer, as well as multiple myeloma.
  • Vitamin-D supplement 400 iu tablets, fat solube prohormone 2 February 2010 18:56 UTC www.physicianformulas.com [Source type: Academic]

^ Higher levels of calcium with adequate vitamin D inhibit fatty acid synthase while diets low in calcium increase fatty acid synthase by as much as five-fold.

[200]
.A report from the National Health and Nutrition Examination Survey (NHANES) involving nearly 5,000 participants found that low levels of vitamin D were associated with an increased risk of peripheral artery disease (PAD).^ Hyperparathyroidism due to low vitamin D levels .

^ Diets low in vitamin A may also increase the risk of developing cancer.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

^ Increased levels of homocysteine, associated with heart disease and possibly Alzheimer's disease.
  • Vitamin D Background - Vitamin D Health Information - NY Times Health 28 January 2010 2:02 UTC health.nytimes.com [Source type: Academic]

.The incidence of PAD was 80% higher in participants with the lowest vitamin D levels (<17.8 ng/mL).^ In July 2008 I was tested for Vitamin D and the level was 22 ng/ml.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Epidemiological data show low levels of vitamin D lead to a higher incidence of breast cancer, colon cancer, prostate cancer, ovarian cancer, as well as multiple myeloma.
  • Vitamin-D supplement 400 iu tablets, fat solube prohormone 2 February 2010 18:56 UTC www.physicianformulas.com [Source type: Academic]

^ We recommend that enough vitamin D be taken daily to maintain 25-hydroxy vitamin D levels at levels normally achieved through summertime sun exposure (50 ng/ml).

[115] .Cholesterol levels were found to be reduced in gardeners in the UK during the summer months.^ They compared change in vitamin D levels with changes in knee pain, physical function and muscle strength during the 30-month study period.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Latitudes higher than 40° have insufficient sunlight to achieve optimum levels of D during six to eight months of the year.

^ In much of the US, which is between 30° and 45° latitude, six months or more during each year have insufficient UV-B sunlight to produce optimal D levels.

[201] .Heart attacks peak in winter and decline in summer in temperate[202] but not tropical latitudes.^ Thus, UV-B is present only during midday hours at higher latitudes, and only with significant intensity in temperate or tropical latitudes.

^ Why the elderly are so much more likely to die from heart attacks in the winter rather than in the summer, 14.

^ As a prolonged 'vitamin D winter', centred on the winter solstice, occurs at many temperate latitudes, Dose response to vitamin D supplementation among postmenopausal African American women - Am J Clin Nutr.

[203] .Calcifediol (25-hydroxy-vitamin D) is implicated in the etiology of atherosclerosis, especially in non - Caucasians.^ We recommend that enough vitamin D be taken daily to maintain 25-hydroxy vitamin D levels at levels normally achieved through summertime sun exposure (50 ng/ml).

^ Abstract: The biochemical parameters associated with vitamin D metabolism, calcium, 25-hydroxy-vitamin D (25OHD) and alkaline phosphatase levels were assessed in 226 out-patients with epilepsy.

^ The 25-hydroxy vitamin D test is the most accurate way to measure how much vitamin D is in your body.In the kidney, 2...
  • Vitamin D | LIVESTRONG.COM 28 January 2010 2:02 UTC www.livestrong.com [Source type: FILTERED WITH BAYES]

[204][205][206][207] .Vitamin D levels are generally higher in the physically fit but are lower in those of tropical origin, this is a confound for any attempt to make a worldwide recommendation for vitamin D. [208] 1,25-Dihydroxycholecalciferol(active serum vitamin D) levels are inversely correlated with coronary calcification[209] moreover one-alpha-hydroxy-cholecalciferol, an active vitamin D analog[210] therapy seems to protect patients from developing vascular calcification.^ Vitamin D and vascular calcification.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Active serum vitamin D levels are inversely correlated with coronary calcification.

^ We recommend that enough vitamin D be taken daily to maintain 25-hydroxy vitamin D levels at levels normally achieved through summertime sun exposure (50 ng/ml).

[211] .African Americans have higher active serum vitamin D levels.^ Active serum vitamin D levels are inversely correlated with coronary calcification.

^ Tanning is associated with optimal vitamin D status (serum 25-hydroxyvitamin D concentration) and higher bone mineral density 1 ,2 ,3 .

^ Higher levels of calcium with adequate vitamin D inhibit fatty acid synthase while diets low in calcium increase fatty acid synthase by as much as five-fold.

[212][213][214] .There are racial differences in the association of coronary calcified plaque[215] in that there is less calcified atherosclerotic plaque in the coronary arteries of African-Americans than in whites.^ The prevalence of serum concentrations of 25(OH)D less than or equal to 15 ng/mL (less than or equal to 37.5 nmol/L) was 10 times greater for the African American women (42.2%) than for the white women (4.2%).

^ Today, most humans only make about a thousand units of vitamin D a day from sun exposure; many people, such as the elderly or African Americans, make much less than that.

^ RESULTS--Overall, subjects with supplementary vitamin E intake of 100 IU per day or greater demonstrated less coronary artery lesion progression than did subjects with supplementary vitamin E intake less than 100 IU per day for all lesions (P = .04) and for mild/moderate lesions (P = .01).

.One study found an elevated risk of ischaemic heart disease in Southern India in individuals whose vitamin D levels were above 89 ng/mL.[132] Freedman et al.^ "Vitamin D deficiency and risk of cardiovascular disease".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Kids who have low vitamin D levels are at serious risk of heart disease in adulthood ...

^ In July 2008 I was tested for Vitamin D and the level was 22 ng/ml.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

.(2010) have found that serum vitamin D correlates in African Americans, but not in Euro-Americans, with calcified atheroscleratic plaque.^ Tanning is associated with optimal vitamin D status (serum 25-hydroxyvitamin D concentration) and higher bone mineral density American Journal of Clinical Nutrition, Vol.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ African Americans, who don't produce as much vitamin D because of their skin pigment, could also benefit significantly from a higher intake.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ A recent review of reports of nutritional rickets found that a majority of cases occurred among young, breastfed African Americans [50].

.Pharmacokinetics of vitamin D toxicity states - "Early assumptions that 1,25(OH)2D3 might cause hypercalcemia in vitamin D toxicity have been replaced by the theories that 25(OH)D3 at pharmacologic concentrations can overcome vitamin D receptor affinity disadvantages to directly stimulate transcription or that total vitamin D metabolite concentrations displace 1,25(OH)2D from vitamin D binding".[216] Freedman et al.^ The effect of 25-D on the vitamin D Receptor ( filelink ) The displacement of a ligand from a receptor is reversible.
  • http://www.marshallprotocol.com/forum2/2572.html 28 January 2010 2:02 UTC www.marshallprotocol.com [Source type: Academic]
  • http://www.marshallprotocol.com/view_topic.php?id=2572&forum_id=2&jump_to=91694#p91694 11 September 2009 3:03 UTC www.marshallprotocol.com [Source type: Academic]

^ Serum concentration of 25(OH)D is the best indicator of vitamin D status.
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]
  • Vitamin D 28 January 2010 2:02 UTC www.hoptechno.com [Source type: Academic]

^ Vitamin D3 could be more than three times as effective as vitamin D2 in raising serum 25(OH)D concentrations and maintaining those levels for a longer time, and its metabolites have superior affinity for vitamin D-binding proteins in plasma [5,39,40].

.(2010) states - "Higher levels of 25-hydroxyvitamin D seem to be positively correlated with aorta and carotid CP in African Americans but not with coronary CP. These results contradict what is observed in individuals of European descent".[217] Recommendations stemming for a single standard for optimal serum 25(OH)D concentrations ignores the differing genetically mediated determinates of serum 25(OH)D and may result in ethnic minorities in Western countries having the results of studies done with subjects not representative of ethnic diversity applied to them.^ "Serum 25-hydroxyvitamin D levels and risk of multiple sclerosis".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Results: Subjects who used a tanning bed had serum 25(OH)D concentrations 90% higher than those of control subjects.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ In institutionalized subjects 25(OH)D levels are often in the deficiency range.

.Vitamin D levels vary for genetically mediated reasons as well as environmental ones.^ I mean yes IF ANY OF US are having problems with low Vitamin D levels i agree with one of the responders to a point ..
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ Research data show low levels of vitamin D lead to a higher incidence of breast cancer, colon cancer, prostate cancer, ovarian cancer, as well as multiple myeloma.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ When these conditions are found in succeeding generations it means the genetics require higher levels of one or both nutrients to optimize health.

[218][219][220][221][222][223] .[224][225] Among descent groups with heavy sun exposure during their evolution, taking supplemental vitamin D to attain the 25(OH)D level associated with optimal health in studies done with mainly European populations may have deleterious outcomes.^ Vitamin D from Sun or supplement pill?
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ It is the optimum level of 25(OH)D that is most strongly associated with general good health.

^ Vitamin D supplementation during Antarctic winter.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

[226] .A review of vitamin D status in India concluded that studies uniformly point to low 25(OH)D levels in Indians despite abundant sunshine, and suggested a public health need to fortify Indian foods with vitamin D might exist.^ Hyperparathyroidism due to low vitamin D levels .

^ Tagged: health vitamin d sunshine .

^ Serum concentration of 25(OH)D is the best indicator of vitamin D status.
  • Dietary Supplement Fact Sheet: Vitamin D 28 January 2010 2:02 UTC ods.od.nih.gov [Source type: Academic]
  • Vitamin D 28 January 2010 2:02 UTC www.hoptechno.com [Source type: Academic]

However the levels found in India are consistent with many other studies of tropical populations which have found that even an extreme amount of sun exposure, such as incured by rural Indians,[227] does not raise 25(OH)D levels to the levels typically found in Europeans,[228][229][230][231][232][233] [234]

Mortality

.Using information from the National Health and Nutrition Examination Survey a group of researchers concluded that having low levels of vitamin D (<17.8 ng/ml) was independently associated with an increase in all-cause mortality in the general population.^ Hyperparathyroidism due to low vitamin D levels .

^ In July 2008 I was tested for Vitamin D and the level was 22 ng/ml.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Generally Celiacs have low B, D, and K vitamin levels due to the severe malabsorption.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

[235] .The study evaluated whether low serum vitamin D levels were associated with all-cause mortality, cancer, and cardiovascular disease (CVD) mortality among 13,331 diverse American adults who were 20 years or older.^ "Vitamin D deficiency and risk of cardiovascular disease".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Kids who have low vitamin D levels are at serious risk of heart disease in adulthood ...

^ Hyperparathyroidism due to low vitamin D levels .

Vitamin D levels of these participants were collected over a 6-year period (from 1988 through 1994), and individuals were passively followed for mortality through the year 2000.
.Among many factors that may be responsible for certain levels of vitamin D having a beneficial effect on all-cause mortality is its effect on telomeres and its potential effect on slowing aging, overall, excess or deficiency in the calcipherol system appear to cause abnormal functioning and premature aging.^ Maybe we all have some common habit/lifestyle that may be responsible for the Vitamin D deficiency.
  • Vitamin D Deficiency ? - Undiagnosed Symptoms - MedHelp 2 February 2010 18:56 UTC www.medhelp.org [Source type: Original source]

^ "Vitamin D deficiency in systemic lupus erythematosus".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

^ Table 2 lists causes and effects of vitamin D deficiency.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

[236][237][238] Shortening of leukocyte telomeres is a marker of aging. .Leukocyte telomere length (LTL) predicts the development of aging-related disease, and length of these telomeres decreases with each cell division and with increased inflammation (more common in the elderly).^ Liver enzyme elevations are more common in patients given large dosage increases over short periods of time, and in patients treated with sustained release formulations.

^ Americans aged 50 and older are at increased risk of developing vitamin D insufficiency [33].

^ Ackerman advised keeping out of the sun if you’re concerned about premature aging or if you’re very fair-skinned due to the increased risk of developing squamous cell carcinoma, a less dangerous form of cancer.

.Research indicates that vitamin D is a potent inhibitor of the proinflammatory response and slows the turnover of leukocytes.^ Available data indicate that vitamin D exerts a biphasic 'dose response' curve on vascular calcification with deleterious consequences not only of vitamin D excess but also of vitamin D deficiency.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ Bioassays of commercial livestock feeds indicate much higher vitamin D contents than the National Research Council recommendation.

^ Now, a University of Missouri nutritional sciences researcher has found that vitamin D deficiency is associated with inflammation, a negative response of the immune system, in healthy women ...

.Higher than average vitamin D levels were also associated with longer leukocyte telomere length, indicating that optimal vitamin D concentrations could play a role in preventing age-related diseases.^ But in fact their vitamin D levels were "markedly higher" than average.
  • Vitamin D benefit : by Ray Sahelian, M.D., Vitamin D deficiency information, Food with vitamin D prevent cancer 28 January 2010 2:02 UTC www.raysahelian.com [Source type: Academic]

^ The role of vitamin D in cancer prevention.
  • NEJM -- Vitamin D Deficiency 28 January 2010 2:02 UTC content.nejm.org [Source type: Academic]

^ Higher serum vitamin D concentrations are associated with longer leukocyte telomere length in women ".
  • Vitamin D Health - Scientific Facts and Correlations 28 January 2010 2:02 UTC www.perciavalle.com [Source type: Academic]

[239]

See also

References

  1. ^ Walter F., PhD. Boron (2003). "The Parathyroid Glands and Vitamin F". Medical Physiology: A Cellular And Molecular Approaoch. Elsevier/Saunders. p. 1094. ISBN 978-1-4160-2328-9. 
  2. ^ a b c d "Dietary Supplement Fact Sheet: Vitamin D". National Institutes of Health. Archived from the original on 2007-09-10. http://www.webcitation.org/5Rl5u0LB5. Retrieved 2007-09-10. 
  3. ^ a b c d e Vitamin D at Merck Manual of Diagnosis and Therapy Professional Edition
  4. ^ van den Berg H (January 1997). "Bioavailability of vitamin D". European Journal of Clinical Nutrition 51 (Suppl 1): S76–9. PMID 9023488. 
  5. ^ Cranney A, Horsley T, O'Donnell S, et al. (August 2007). "Effectiveness and safety of vitamin D in relation to bone health". Evidence Report/technology Assessment (158): 1–235. PMID 18088161. 
  6. ^ Freidl A, Ward S, Rubin RN. What’s The “Take Home”?[http://www.consultantlive.com/display/article/10162/1532408 Fracture after fall in a middle-aged African American woman.] Consultant. 2010;50(3):137-139.
  7. ^ Silver J, Russell J, Sherwood LM (June 1985). "Regulation by vitamin D metabolites of messenger ribonucleic acid for preproparathyroid hormone in isolated bovine parathyroid cells". Proceedings of the National Academy of Sciences of the United States of America 82 (12): 4270–3. PMID 3858880. 
  8. ^ Silver J, Naveh-Many T, Mayer H, Schmelzer HJ, Popovtzer MM (November 1986). "Regulation by vitamin D metabolites of parathyroid hormone gene transcription in vivo in the rat". The Journal of Clinical Investigation 78 (5): 1296–301. doi:10.1172/JCI112714. PMID 3771798. 
  9. ^ a b Tavera-Mendoza LE, White JH (November 2007). "Cell defenses and the sunshine vitamin". Sci. Am. 297 (5): 62–5, 68–70, 72. doi:10.1038/scientificamerican1107-62. PMID 17990825. http://www.sciam.com/article.cfm?id=cell-defenses-and-the-sunshine-vitamin. 
  10. ^ Dorland's Illustrated Medical Dictionary, under Vitamin (Table of Vitamins)
  11. ^ History of Vitamin D University of California, Riverside, Vitamin D Workshop.
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Simple English

Vitamin D is a vitamin. Vitamin D controls the levels of calcium ions and phosphates in the blood in the intestines. It helps bones grow and form. It is also good for the immune system. In total, there are 5 vitamins, D1 to D5. The most common ones are D2 and D3 (see image). It is in fish-liver oils and fortified milk. If a person lacks vitamin D, they have a higher chance of getting rickets and having soft bones. Vitamin D is found in a narrow range of foods. Good food sources are oily fish and eggs. Other food sources include fortified foods such as margarine, breakfast cereals and powdered milk. But we get most of our vitamin D from sunlight on our skin. This is because the vitamin forms under the skin in reaction to sunlight. Vitamin D is a fat-soluble vitamin. This means you do not need it every day because any of the vitamin your body does not need immediately is stored for future use. Most people get all the vitamin D they need from their diet and sun. However, if you are pregnant, breastfeeding or elderly you should take 10 micrograms (0.01 mg) of vitamin D each day. Vitamin D has a number of important functions. For example it helps regulate the amount of calcium and phosphate in the body, and calcium and phosphate are needed to help keep bones and teeth healthy.

If you take too little, It can lead to diseases such as rickets ( slow growth and deformity of long bones), osteoporosis (reduced density of bones, which causes bones to break.)

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Up to date as of December 15, 2010

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