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Vitamin D toxicity, policy, and science. Vieth R. J Bone Miner Res. 2007 Dec;22 Suppl 2:V64-8. Review. PMID: 18290725 doi: 10.1359/jbmr.07s221

Holick, M. F., MacLaughlin, J. A. & Doppelt, S. H. (1981) Factors that influence the cutaneous photosynthesis of previtamin D3. Science 211:590-593 When human skin was exposed to simulated solar ultraviolet radiation, epidermal 7-dehydrocholesterol was converted to previtamin D3. During prolonged exposure to simulated solar ultraviolet radiation, the synthesis of previtamin D3 reached a plateau at about 10 to 15 percent of the original 7-dehydrocholesterol content, and previtamin D3 was photoisomerized to two biologically inert isomers, lumisterol3 and tachysterol3. Increases either in skin melanin concentration or in latitude necessitated increases in the exposure time to simulated solar ultraviolet radiation required to maximize the formation, but not the total content, of previtamin D3. In order of importance, the significant determinants limiting the cutaneous production of previtamin D3 are (i) photochemical regulation, (ii) pigmentation, and (iii) latitude.

Dietary Reference Intakes for Vitamin D (1997). National Academy of Sciences. Institute of Medicine. Food and Nutrition Board.

Houston DK, Cesari M, Ferrucci L, Cherubini A, Maggio D, Bartali B, Johnson MA, Schwartz GG, Kritchevsky SB. Association between vitamin D status and physical performance: the InCHIANTI study. J Gerontol A Biol Sci Med Sci. 2007 Apr;62(4):440-6. PMID:

One of the leading company cnlab.ca is the manufacture of such nutritional supplements, which at the other hand provides customs manufacturing and OEM service for not only nutritional soft gel products but also tablet, hard gelatin capsules. It is a company of Private label in China who understands the science and cultures of natural health supplements.

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.

This article discusses our experience at the one-day Institute of Medicine workshop on vitamin D and calcium. Both of us had an opportunity to make comments before the committee. Here are Paul's comments and slides and here are Amy's comments and slides. Note that our 2009 paper in Autoimmunity Reviews[1] discusses some of the science we allude to in further detail.

The panel selected to analyze the health claims is being criticized for not including the medical researchers whose work prompted intense scientific interest in the nutrient in the first place. "If you were publicly in favour of vitamin D, you were not included, and I find that outrageous," said Reinhold Vieth, a professor in the department of nutritional sciences at the University of Toronto, and one of Canada's leading experts on the nutrient.

This DRI report presents calcium, phosphorus, magnesium, vitamin D, and fluoride, all of which have key roles in developing and maintaining bone and other calcified tissues in the body. View or download the entire 454 page document or just selected sections below, or find information for obtaining the book version. Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride (1997) National Academy of Sciences. Institute of Medicine. Food and Nutrition Board.

A recent Wall Street Journal article "Defending Against Disease -- With Vitamin D New Studies Suggest It Isn't Just Bones That Might Benefit" by the wonderful Melinda Beck highlights benefits of Vitamin D3. In TYP, we've known the benefits for years :) but it's nice to see the rest of the world catching up. The benefits of Vitamin D3 are potent, powerful immunomodulation -- to the point where autoimmune diseases, viral and bacterial infections and cancer are effectively reduced. What is the value for heart disease and diabetes prevention? In hemodialysis patients, great lessons are can be learned. Nephrologists often describe patients with severe (stage 5) chronic kidney disease (CKD) patients on hemodialysis as having 'hearts of stone, blood vessels of glass.' Unfortunately over 70% of chronic hemodialysis patients have coronary artery disease (and Lp(a)). What medical science shows is that Agatston coronary calcification scores can be dramatically reduced when vitamin D is replenished and calcium is restricted. Sevelamer (Renagel) is a calcium-free, metal-free polymer phosphate binder. In 52-weeks, calcium restriction, a phosphate-binder and vitamin D resulted in one individual in a 21% reduction in Agatston CAC score (from 968 to 756; see Figure 2).

I have been inundated with letters asking about Professor Marshall's recent "discovery." Some have written that to say they have stopped their vitamin D and are going to avoid the sun in order to begin the "Marshall protocol." The immediate cause of this angst is two publications, a press article in Science Daily about Professor Marshall's "study" (which is no study but simply an opinion) in BioEssays. Dr. Trevor Marshall has two degrees, both in electrical engineering

Designed with practicing dermatologists, dermatology trainees, physicians, and scientists interested in photoprotection in mind, this concise and highly illustrated guide provides the latest knowledge of photoprotection in dermatology and cosmetic science. Clinical Guide to Sunscreens and Photoprotectionalso addresses recent important international and domestic regulatory activity and requirements on the use of novel sun protective chemicals and proper labeling of products to ensure increased consumer awareness.This concisely written, problem-oriented text explores See chapter by Bischoff-Ferrari et al. from page 119 dealing with what dose is needed for 25(OH)D level of 80 nmol/l in 97% of population

25(OH)D Serum levels decline with age earlier in women than in men and less efficiently prevent compensatory hyperparathyroidism in older adults. Maggio D, Cherubini A, Lauretani F, Russo RC, Bartali B, Pierandrei M, Ruggiero C, Macchiarulo MC, Giorgino R, Minisola S, Ferrucci L. J Gerontol A Biol Sci Med Sci. 2005 Nov;60(11):1414-9. PMID: 16339327 Conclusions. These findings suggest that the age-associated fall of serum 25(OH)D starts earlier in women than in men and that higher levels of 25(OH)D are required in older compared to younger persons to avoid the age-associated compensatory hyperparathyroidism.

Vitamin D and cancer mini-symposium: the risk of additional vitamin D. Vieth R. Ann Epidemiol. 2009 Jul;19(7):441-5. Epub 2009 Apr 11. Review. PMID: 19364661 Conclusion The results of well-conducted trials of vitamin D lead to the conclusion that the current U.S. National Academy of Sciences-Institute of Medicine upper limit for vitamin D intake of 2000IU per day 1, 37 is excessively conservative. That intake would raise serum 25(OH)D by an average of about 50 nmol/L (20 ng/mL), well within the safe range of serum 25(OH)D concentrations that extends to 500 nmol/L (200 ng/mL). Intake of 4,000IU per day would raise serum 25(OH)D by an average of about 100 nmol/L (40 ng/mL). Even prolonged physiologic-replacement intake of 10,000IU per day of vitamin D3 would pose no known risk of adverse effects in virtually all adults.

According to a recent study in the Archives of Internal Medicine, 75 percent of Americans do not get enough Vitamin D. Researchers have found that the deficiency may negatively impact immune function and cardiovascular health and increase cancer risk. 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.

ScienceDaily (Apr. 8, 2009) - According to a recent study in the Archives of Internal Medicine, 75 percent of Americans do not get enough Vitamin D. Researchers have found that the deficiency may negatively impact immune function and cardiovascular health and increase cancer risk. 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.

P.T. Liu, S. Stenger, H. Li, L. Wenzel, B.H. Tan, S.R. Krutzik, M.T. Ochoa, J. Schauber, K. Wu, C. Meinken, et al.\nVitamin D3-Triggered Antimicrobial Response--Another Pleiotropic Effect beyond Mineral and Bone Metabolism: Toll-Like Receptor Triggering of a Vitamin D-Mediated Human Antimicrobial Response. Science 311: 1770-1773, 2006\nJ. Am. Soc. Nephrol., November 1, 2006; 17(11): 2949 - 2953.

Chen TC, Chimeh F, Lu Z, Mathieu J, Person KS, Zhang A, Kohn N, Martinello S, Berkowitz R, Holick MF. Factors that influence the cutaneous synthesis and dietary sources of vitamin D. Arch Biochem Biophys. 2007 Apr 15;460(2):213-7. Epub 2007 Jan 8. PMI

Lu Z, Chen TC, Zhang A, Persons KS, Kohn N, Berkowitz R, Martinello S, Holick MF. An evaluation of the vitamin D3 content in fish: Is the vitamin D content adequate to satisfy the dietary requirement for vitamin D? J Steroid Biochem Mol Biol. 2007 Mar;