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Use of vitamin D in clinical practice. Cannell JJ, Hollis BW. Altern Med Rev. 2008 Mar;13(1):6-20. PMID: 18377099 The recent discovery--from a meta-analysis of 18 randomized controlled trials--that supplemental cholecalciferol (vitamin D) significantly reduces all-cause mortality emphasizes the medical, ethical, and legal implications of promptly diagnosing and adequately treating vitamin D deficiency. Not only are such deficiencies common, and probably the rule, vitamin D deficiency is implicated in most of the diseases of civilization. Vitamin D's final metabolic product is a potent, pleiotropic, repair and maintenance, seco-steroid hormone that targets more than 200 human genes in a wide variety of tissues, meaning it has as many mechanisms of action as genes it targets. One of the most important genes vitamin D up-regulates is for cathelicidin, a naturally occurring broad-spectrum antibiotic. Natural vitamin D levels, those found in humans living in a sun-rich environment, are between 40-70 ng per ml, levels obtained by few modern humans. Assessing serum 25-hydroxy-vitamin D (25(OH)D) is the only way to make the diagnosis and to assure treatment is adequate and safe. Three treatment modalities exist for vitamin D deficiency: sunlight, artificial ultraviolet B (UVB) radiation, and vitamin D3 supplementation. Treatment of vitamin D deficiency in otherwise healthy patients with 2,000-7,000 IU vitamin D per day should be sufficient to maintain year-round 25(OH)D levels between 40-70 ng per mL. In those with serious illnesses associated with vitamin D deficiency, such as cancer, heart disease, multiple sclerosis, diabetes, autism, and a host of other illnesses, doses should be sufficient to maintain year-round 25(OH)D levels between 55 -70 ng per mL. Vitamin D-deficient patients with serious illness should not only be supplemented more aggressively than the well, they should have more frequent monitoring of serum 25(OH)D and serum calcium. Vitamin D should always be

Circulating vitamin D3 and 25-hydroxyvitamin D in humans: An important tool to define adequate nutritional vitamin D status. Hollis BW, Wagner CL, Drezner MK, Binkley NC. J Steroid Biochem Mol Biol. 2007 Mar;103(3-5):631-4. Epub 2007 Jan 10. PMID: 17218096 In the present study, we sought to investigate what circulating 25(OH)D levels would result in populations exhibiting no substrate limitations to the vitamin D-25-hydroxylase. To perform this, we chose two distinct populations. The first were individuals from a year-found sunny environment who spent a good deal of time outdoors. The second were a group of lactating women receiving a substantial daily oral dose of vitamin D3. Surprisingly, a study such as this previously had not been undertaken. There are several reasons for this. First, finding a group of sun-exposed individuals is not an easy task; in fact, we had to go to Hawaii to find them. Secondly, very few studies have been performed where subjects actually received adequate vitamin D3 supplementation to make them replete. Finally, it is very difficult and costly to measure circulating vitamin D3 and relate it to circulating 25(OH)D. The results of our study are far-reaching. This study also demonstrates that individuals can be vitamin D deficient with significant sun exposure if the skin area exposed is limited as was suggested several years ago (19). Finally, whether one receives their vitamin D3 orally or through UV exposure, the vitamin D-25-hydroxylase appears to handle it in an equivalent fashion with respect to maintaining circulating 25(OH)D levels. Thus, we believe that the relationship between circulating vitamin D and 25(OH)D may define adequate nutritional vitamin D status.

"Hi! This is Amy Proal. I wrote the article referenced at the start of the thread about vitamin D. Dr. Marshall is not concerned with vitamin D toxicity. Rather his molecular modeling research has clarified the actions of the two vitamin D metabolites 25-D and 1,25-D. The Vitamin D Receptor (VDR) is a fundamental receptor of the body - it controls the expression thousands of genes, as well as the activity of the innate immune system and the antimicrobial peptides. If you think of the VDR as a switch, 25-D (which is a corticosteroid) turns it off (inactivates it) and 1,25-D turn it on (activates it). What is commonly believed among vitamin D researchers is that if people supplement with extra vitamin D it will be converted into 1,25-D and activate the VDR. Unfortunately, Marshall's work revealed that the type of vitamin D derived from supplements and sun remains, for the most part, in it's precursor form 25-D. This means that the extra vitamin D we get from fortified food products and supplements is turning the VDR off, not on. That causes a decrease in immune function and gene transcription."

Vitamin D: a D-Lightful health perspective. Holick MF. Nutr Rev. 2008 Oct;66(10 Suppl 2):S182-94. Review. PMID: 18844847 DOI: 10.1111/j.1753-4887.2008.00104.x Sunlight provides most humans with their vitamin D requirement. Adequate vitamin D(3) by synthesis in the skin or from dietary and supplemental sources is essential for bone health throughout life. Vitamin D deficiency is defined as a 25(OH)D concentration 30 ng/mL (75 nmol/L), and insufficiency as 21-29 ng/mL. Vitamin D deficiency and insufficiency has been linked to a wide variety of chronic diseases including common cancers, autoimmune, cardiovascular, and infectious diseases. Healthcare professionals need to be aware of the vitamin D deficiency pandemic. Guidelines for sensible sun exposure and supplemental vitamin D of 800-1000 IU/day are needed.

"One of the surprises over the past year has been all the research regarding Vitamin D and brain health. Give that many people are spending less time outdoors and more time in front of their computers, we all should be concerned, as Vitamin D comes in part from our exposure to the sun. Low Vitamin D levels have been associated with pain, depression, MS, cancer and now perhaps even dementia. Here are the results of a new study that should cause all of us to pay attention. I frequently check the Vitamin D levels in my patients and frrequently see that they are below the optimal level. Get your levels checked if you have any of these concerns. A new large-scale senior population study has found that a lack of vitamin D in the elderly could be linked to cognitive impairment. The study, conducted on almost 2,000 adults over the age of 65, is the first of its scale to identify this relationship, and prompted researchers to suggest vitamin D supplementation as a possible means of reducing the risk of dementia. "

"We are fond of grumbling about Britain's grey skies, but there may be a good medical reason for doing so. It seems the dreary weather is bad for our hearts - worse, even, than raised cholesterol and an unhealthy diet. That's the controversial claim being made by Dr David Grimes, a gastroenterologist from Blackburn. He's been gazing at the sky for 20 years for clues about why his patients get more sick than those in the south of the country. And what he's found turns key assumptions about heart disease on their head. 'It's not diet or cholesterol levels that raise your risk of heart disease,' he claims. 'It's where you live. People in the north are more likely to be ill because they get less sunshine Basically they are suffering from 'latitude' sickness. The link is vitamin D. While we get some from our diet, the main source is the sun - sunlight converts a compound in the skin into vitamin D, so the amount you make is directly related to the amount of sunshine you get. In a new book Dr Grimes argues the higher the level of vitamin D in your blood, the lower your risk of heart disease and a range of other illnesses. If he's right, what we need is not diet and lifestyle advice, but food fortified with vitamin D. For years the vitamin was thought to be useful only for preventing rickets. So how does he treat them? 'You can do it with diet,' he says 'One Bangladeshi woman eats oily fish every day and now has a vitamin D blood level of 40. 'We give supplements of 1,000 international units (IU) a day or we can give an injection of 300,000 IU that lasts for a year. 'The patients respond well,' says Grimes 'but what's needed is a proper controlled, long-term trial and who is going to fund that? Not a drug company.'"

Vitamin D is safe when used in physiological doses (those used by Nature). Physiological doses are 3,000-5,000 IU/day, from all sources (sun, diet and supplements). Should hypercalcemia occur with such doses, it is due to vitamin D hypersensitivity syndrome, not vitamin D toxicity. Vitamin D hypersensitivity syndromes include conditions such as primary hyperparathyroidism, occult cancers (especially lymphoma) or granulomatous disease (especially sarcoidosis). In such cases, treatment of vitamin D deficiency should be done under the care of a knowledgeable physician. A serum 25(OH)D, serum 1,25(OH)D, PTH and SMA will lead the clinician in the right direction.

Benefits of Vitamin D Supplementation Joel M. Kauffman, Ph.D. Journal of American Physicians and Surgeons Volume 14 Number 2 - Summer 2009 Clinical trials show that vitamin D supplementation at higher levels than previously recommended is beneficial for many conditions. It decreases the frequency of falls and fractures, helps prevent cardiovascular disease, and reduces symptoms of colds or influenza. Benefits are also seen in diabetes mellitus, multiple sclerosis, Crohn disease, pain, depression, and possibly autism. Sunlight does not cause an overdose of vitamin D production, and toxicity from supplementation is rare. Dose recommendations are increasing, but appear to be lagging the favorable trial results. A number of common drugs deplete vitamin D levels, and others may limit its biosynthesis from sunlight. People with adequate levels from sun exposure will not benefit from supplementation. While dietary intake is helpful, supplementation is better able to raise serum 25-hydroxyvitamin D , the major circulating metabolite, to the level now thought adequate, 30-50 ng/mL. Where there is inadequate daily sun exposure, oral doses of 1,000-2,000 IU/d are now considered routine, with much higher doses (up to 50,000 IU) for rapid repletion now considered safe.

A New Zealand study has found that South Asian women with insulin resistance improved markedly after taking vitamin D supplements Nutrition researcher Pamela von Hurst of the Institute of Food, Nutrition and Human Health at Albany, said while diet and exercise played a major part in the onset of type-2 diabetes, her findings reinforced the importance of vitamin D from the sun and supplements to prevent type-2 diabetes. Initial screening of 235 Auckland women from India, Pakistan and Sri Lanka aged 20 and older, revealed 47 per cent were insulin deficient and 84 per cent were vitamin D deficient. The 81 recruited for the study were split into two groups for a randomised controlled trial and given a vitamin D supplement or placebo. As well as an improvement in insulin resistance among those who took vitamin D for six months, Ms Von Hurst said post-menopausal women in the study also showed a reduced rate of bone breakdown.

In the last post, we talked about the new report on vitamin D and cancer from the International Agency for Research into Cancer (IARC). In this one, we'll summarise what the report has to say on the balance between getting enough vitamin D through sun exposure and reducing the risk of skin cancer by being SunSmart. IARC calls for more trials to really pin down the effects of vitamin D supplements - either positive or negative - depending on how much vitamin D people already have in their system. Until then, they feel that there is no solid basis for changing any existing recommendations about vitamin D.

Robert P. Heaney is John A. Creighton University Professor, Creighton University, Omaha, Nebraska, United States. Hominid evolution took place in an environment (equatorial East Africa) that provided a superabundance of both calcium and vitamin D, the first in available foods and the second through conversion of 7-dehydrocholesterol to pre-vitamin D in the skin, a reaction catalysed by the intense solar ultraviolet (UV) radiation. Seemingly as a consequence, the evolving human physiology incorporated provisions to prevent the potential of toxic excesses of both nutrients. For vitamin D the protection was of two sorts: skin pigmentation absorbed the critical UV wavelengths and thereby limited dermal synthesis of cholecalciferol; and slow delivery of vitamin D from the skin into the bloodstream left surplus vitamin in the skin, where continuing sun exposure led to its photolytic degradation to inert compounds. For calcium, the adaptation consisted of very inefficient calcium absorption, together with poor to absent systemic conservation. The latter is reflected in unregulated dermal calcium losses, a high sensitivity of renal obligatory calcium loss to other nutrients in the diet and relatively high quantities of calcium in the digestive secretions. Today, chimpanzees in the original hominid habitat have diets with calcium nutrient densities in the range of 2 to 2.5 mmol per 100 kcal, and hunter-gatherer humans in Africa, South America and New Guinea still have diets very nearly as high in calcium (1.75 to 2 mmol per 100 kcal) (Eaton and Nelson, 1991). With energy expenditure of 3 000 kcal per day (a fairly conservative estimate for a contemporary human doing physical work), such diets would provide substantially in excess of 50 mmol of calcium per day. By contrast, median intake in women in North America and in many European countries today is under 15 mmol per day. Two factors altered the primitive situation: the migration of humans from Africa to higher latitude

Vitamin D treatment in multiple sclerosis. Myhr KM. J Neurol Sci. 2009 Jun 22. [Epub ahead of print] PMID: 19549608 doi:10.1016/j.jns.2009.05.002 Epidemiological evidence combined with clinical and laboratory analyses, and experimental animal models, suggest a possible influence of vitamin D on MS susceptibility as well as clinical disease activity. Supplement with vitamin D may reduce the risk of developing MS. An intervention may also reduce the risk of conversion from a first clinical event suggestive of MS to clinical definite MS, as well as reduce the relapse rate among patients with relapsing remitting MS. More studies are, however, needed to determine optimal dose and serum level for vitamin D, as well as target populations and optimal timing for intervention.

Athletic performance and vitamin D. Cannell JJ, Hollis BW, Sorenson MB, Taft TN, Anderson JJ. Med Sci Sports Exerc. 2009 May;41(5):1102-10. Review. PMID: 19346976 doi: 10.1249/MSS.0b013e3181930c2b Conclusions: Vitamin D may improve athletic performance in vitamin D-deficient athletes. Peak athletic performance may occur when 25(OH)D levels approach those obtained by natural, full-body, summer sun exposure, which is at least 50 ng·mL-1. Such 25(OH)D levels may also protect the athlete from several acute and chronic medical conditions.

Feb. 23, 2009 -- A walk in the sun may be better than popping a vitamin C tablet for boosting your chances of preventing the common cold or flu.\n\nA new study adds to mounting evidence that vitamin C may have been stealing the spotlight all these years from the real cold fighter, vitamin D.

This web site is dedicated to vitamin D and cancer. This is because exciting new research indicates that vitamin D-whether produced in the skin as a result of exposure to ultraviolet radiation (from sunlight or sun lamps) or obtained from supplementation with cholecalciferol (vitamin D3)-may help cancer patients. However, the research is far from complete.

"Women from India, Pakistan and Sri Lanka with insulin resistance showed marked improvement after taking vitamin D supplements, says a study. Von Hurst, nutrition lecturer at the Institute of Food, Nutrition and Human Health at Albany, conducted the study for her doctoral thesis. Insulin resistance is largely symptom-free and sufferers are unaware of their condition. 'Once it has fully developed into type-2 diabetes, it can be treated, but not cured,' says Von Hurst. Von Hurst says that while diet and exercise play a major part in the onset of type-2 diabetes, her findings reinforce the importance of vitamin D from the sun and supplements to prevent type-2 diabetes. She also found evidence of vitamin D increasing bone strength in older women. "

Vitamin D deficiency: a worldwide problem with health consequences. Holick MF, Chen TC. Am J Clin Nutr. 2008 Apr;87(4):1080S-6S. Review. PMID: 18400738 A reevaluation needs to take place of what the adequate intakes of vitamin D should be for children and adults. The literature over the past decade suggests that the Institute of Medicine recommendations in 1997 (83) are inadequate, and some experts including us suggest that both children and adults should take ≥800-1000 IU vitamin D/d from dietary and supplemental sources (4, 9, 77) when sunlight is unable to provide it. This recommendation, however, has not yet been embraced either by official government or pediatric organizations in the United States, Canada, or Europe for either children or adults.

Vitamin D is very important for bone health because it plays a role in calcium absorption in the stomach and digestive tract.

"It's well known that African Americans have low levels of vitamin D in their blood. In fact, this seems to be generally true for humans of tropical origin. In a study from Hawaii, vitamin D status was assessed in healthy, visibly tanned young adults who averaged 22.4 hours per week of unprotected sun exposure. Yet 51% had levels below the current recommended minimum of 75 nmol/L (Binkley et al., 2007). In a study from south India, levels below 50 nmol/L were found in 44% of the men and 70% of the women. The subjects are described as "agricultural workers starting their day at 0800 and working outdoors until 1700 with their face, chest, back, legs, arms, and forearms exposed to sunlight" (Harinarayan et al., 2007). In a study from Saudi Arabia, levels below 25 nmol/L were found in respectively 35%, 45%, 53%, and 50% of normal male university students of Saudi, Jordanian, Egyptian, and other origins (Sedrani, 1984)."

The association of solar ultraviolet B (UVB) with reducing risk of cancer: multifactorial ecologic analysis of geographic variation in age-adjusted cancer mortality rates. Grant WB, Garland CF. Anticancer Res. 2006 Jul-Aug;26(4A):2687-99. PMID: 16886679 CONCLUSION: These results provide additional support for the hypothesis that solar UVB, through photosynthesis of vitamin D, is inversely-associated with cancer mortality rates, and that various other cancer risk-modifying factors do not detract from this link. It is thought that sun avoidance practices after 1980, along with improved cancer treatment, led to reduced associations in the latter period. The results regarding solar UVB should be studied further with additional observational and intervention studies of vitamin D indices and cancer incidence, mortality and survival rates.