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Factors that influence the cutaneous synthesis and dietary sources of vitamin D. Chen TC, Chimeh F, Lu Z, Mathieu J, Person KS, Zhang A, Kohn N, Martinello S, Berkowitz R, Holick MF. Arch Biochem Biophys. 2007 Apr 15;460(2):213-7. Epub 2007 Jan 8. PMID: 17254541 doi: 10.1016/j.abb.2006.12.017 Vitamin D is rare in food. Among the vitamin D-rich food, oily fish are considered to be one of the best sources. Therefore, we analyzed the vitamin D content in several commonly consumed oily and non-oily fish. The data showed that farmed salmon had a mean content of vitamin D that was ~25% of the mean content found in wild caught salmon from Alaska, and that vitamin D2 was found in farmed salmon, but not in wild caught salmon. The results provide useful global guidelines for obtaining sufficient vitamin D3 by cutaneous synthesis and from dietary intake to prevent vitamin D deficiency and its health consequences.ensuing illness, especially, bone fractures in the elderly.

nfluence of season and latitude on the cutaneous synthesis of vitamin D3: exposure to winter sunlight in Boston and Edmonton will not promote vitamin D3 synthesis in human skin. Webb AR, Kline L, Holick MF. J Clin Endocrinol Metab. 1988 Aug;67(2):373-8. PMID: 2839537 doi:10.1210/jcem-67-2-373 These results quantify the dramatic influence of changes in solar UVB radiation on cutaneous vitamin D3 synthesis and indicate the latitudinal increase in the length of the "vitamin D winter" during which dietary supplementation of the vitamin may be advisable.

Childhood sun exposure influences risk of multiple sclerosis in monozygotic twins. Islam T, Gauderman WJ, Cozen W, Mack TM. Neurology. 2007 Jul 24;69(4):381-8. PMID: 17646631 Conclusion: Early sun avoidance seems to precede the diagnosis of multiple sclerosis (MS). This protective effect is independent of genetic susceptibility to MS.

Factors that influence the cutaneous synthesis and dietary sources of vitamin D.\nChen TC, Chimeh F, Lu Z, Mathieu J, Person KS, Zhang A, Kohn N, Martinello S, Berkowitz R, Holick MF.\nArch Biochem Biophys. 2007 Apr 15;460(2):213-7. Epub 2007 Jan 8.\nPMID: 17254541\ndoi:10.1016/j.abb.2006.12.017\n

Environmental factors that influence the cutaneous production of vitamin D. Holick MF. Am J Clin Nutr. 1995 Mar;61(3 Suppl):638S-645S. Review. PMID: 7879731

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

Vitamin D receptor allele combinations influence genetic susceptibility to type 1 diabetes in Germans. Pani MA, Knapp M, Donner H, Braun J, Baur MP, Usadel KH, Badenhoop K. Diabetes. 2000 Mar;49(3):504-7. PubMed PMID: 10868975. doi: 10.2337/diabetes.49.3.504

Vitamin D receptor gene polymorphisms influence susceptibility to type 1 diabetes mellitus in the Taiwanese population. Chang TJ, Lei HH, Yeh JI, Chiu KC, Lee KC, Chen MC, Tai TY, Chuang LM. Clin Endocrinol (Oxf). 2000 May;52(5):575-80. PMID: 10792336 DOI: 10.1046/j.1365-2265.2000.00985.x CONCLUSIONS Vitamin D receptor gene polymorphisms were associated with type 1 diabetes in a Taiwanese population. However, functional studies are needed to establish the role of the vitamin D receptor in the pathogenesis of type 1 diabetes mellitus.

The role of vitamin D and calcium in type 2 diabetes. A systematic review and meta-analysis. Pittas AG, Lau J, Hu FB, Dawson-Hughes B. J Clin Endocrinol Metab. 2007 Jun;92(6):2017-29. Epub 2007 Mar 27. Review. PMID: 17389701 .CONCLUSIONS: Vitamin D and calcium insufficiency may negatively influence glycemia, whereas combined supplementation with both nutrients may be beneficial in optimizing glucose metabolism.

Vitamin D2 is as effective as vitamin D3 in maintaining circulating concentrations of 25-hydroxyvitamin D. Holick MF, Biancuzzo RM, Chen TC, Klein EK, Young A, Bibuld D, Reitz R, Salameh W, Ameri A, Tannenbaum AD. J Clin Endocrinol Metab. 2008 Mar;93(3):677-81. Epub 2007 Dec 18. PMID: 18089691 Conclusion: A 1000 IU dose of vitamin D2 daily was as effective as 1000 IU vitamin D3 in maintaining serum 25-hydroxyvitamin D levels and did not negatively influence serum 25-hydroxyvitamin D3 levels. Therefore, vitamin D2 is equally as effective as vitamin D3 in maintaining 25-hydroxyvitamin D status.

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.

Vitamin D and type 2 diabetes: are we ready for a prevention trial? Scragg R. Diabetes. 2008 Oct;57(10):2565-6. PMID: 18820212 doi: 10.2337/db08-0879 Despite evidence from the current article (3) and the Finnish study (17), doubts still remain about whether low vitamin status is a cause of type 2 diabetes. Further cohort studies are required, assessing baseline vitamin D status using blood 25(OH)D to be sure that the Ely and Finnish studies are not false-positive results. Glucose clamp studies are also required because we are still not sure of the mechanism influenced by vitamin D-whether it is insulin resistance, secretion, or both. But most importantly, given that nearly three decades have passed since the first studies linking vitamin D with insulin metabolism (6,7), well-designed clinical trials of the effect of vitamin D supplementation on glycemia status and diabetes risk are urgently required to settle this question. And they need to prevent past mistakes. In particular, the vitamin D dose given in such trials needs to be high enough-above 2,000 IU per day (19)-to raise blood 25(OH)D levels above 80 nmol/l because diabetes risk is lowest at this level (9,20). If well-designed trials are carried out and confirm a protective effect from vitamin D, it could be used by the general population as a simple and cheap solution to help prevent the diabetes epidemic.

SSeason of diagnosis is a prognostic factor in Hodgkin's lymphoma: a possible role of sun-induced vitamin D. Porojnicu AC, Robsahm TE, Ree AH, Moan J. Br J Cancer. 2005 Sep 5;93(5):571-4. PMID: 16136030 doi:10.1038/sj.bjc.6602722 Epidemiological data for this period indicate that season of diagnosis is a strong prognostic factor for Hodgkin's lymphoma, with approximately 20% lower case fatality for patients diagnosed during autumn vs winter diagnosis (RR = 0.783, 95% CI,-0.62 to 0.99; P = 0.041). Notably, the improved autumnal survival rate was higher than 60% (RR = 0.364, 95% CI, -0.15 to 0.87; P = 0.025) for patients younger than 30 years. This finding may be related to higher endogenous levels of vitamin D in autumn, with a favourable influence on the conventional therapy. In conclusion, we have found that the prognosis of Hodgkin's lymphoma is significantly correlated with the season of diagnosis, particularly for patients younger than 30 years. This seasonal effect is presumably due to the vitamin D3 synthesis in skin during sun exposure. The present findings should encourage further investigations of the possible adjuvant role of vitamin D derivatives in cancer therapy

Vitamin D and skin physiology: a D-lightful story. Holick MF, Chen TC, Lu Z, Sauter E. J Bone Miner Res. 2007 Dec;22 Suppl 2:V28-33. PMID: 18290718 doi: 10.1359/jbmr.07s211 Very few foods naturally contain vitamin D, and those that do have a very variable vitamin D content. Recently it was observed that wild caught salmon had between 75% and 90% more vitamin D(3) compared with farmed salmon. The associations regarding increased risk of common deadly cancers, autoimmune diseases, infectious diseases, and cardiovascular disease with living at higher latitudes and being prone to vitamin D deficiency should alert all health care professionals about the importance of vitamin D for overall health and well being. Humans have depended on sunlight for their vitamin D requirement. The impact of season, time of day, and latitude on vitamin D synthesis is well documented.(2,3) We now report that altitude also has a dramatic influence on vitamin D3 production and that living at altitudes above 3500 m permits previtamin D3 production at a time when very little is produced at latitudes below 3400 m. It was surprising that, at 27° N in Agra (169 M), little previtamin D3 production was observed. However, there was significant air pollution that caused a haze over the city. It is likely the ozone and other UVB-absorbing pollutants in the air prevented the solar UVB photons from reaching the earth's surface to produce previtamin D3.

Serum 25-hydroxyvitamin D status of vegetarians, partial vegetarians, and nonvegetarians: the Adventist Health Study-2. Chan J, Jaceldo-Siegl K, Fraser GE. Am J Clin Nutr. 2009 May;89(5):1686S-1692S. Epub 2009 Apr 1. PMID: 19339396 Conclusions: s25(OH)D concentrations were not associated with vegetarian status. Other factors, such as vitamin D supplementation, degree of skin pigmentation, and amount and intensity of sun exposure have greater influence on s25(OH)D than does diet.

The Standing Committee of European Doctors (CPME) is preparing a vitamin D policy paper it hopes can influence European national associations considering vitamin D medical recommendations. PA International Foundation is hosting an event on the topic in Bruges, Belgium, on October 6, its 14th workshop to be held on the matter. The CPME draft paper will be presented at the convention attended by doctors, scientists, patient groups, media representatives and politicians.

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.

Circulating 25-hydroxyvitamin d levels and survival in patients with colorectal cancer. Ng K, Meyerhardt JA, Wu K, Feskanich D, Hollis BW, Giovannucci EL, Fuchs CS. J Clin Oncol. 2008 Jun 20;26(18):2984-91. PMID: 18565885 DOI: 10.1200/JCO.2007.15.1027 Conclusion Among patients with colorectal cancer, higher prediagnosis plasma 25(OH)D levels were associated with a significant improvement in overall survival. Further study of the vitamin D pathway and its influence on colorectal carcinogenesis and cancer progression is warranted.

Vitamin D: the alternative hypothesis. Albert PJ, Proal AD, Marshall TG. Autoimmun Rev. 2009 Jul;8(8):639-44. Epub 2009 Feb 12. Review. PMID: 19393200 Emerging molecular evidence suggests that symptomatic improvements among those administered vitamin D is the result of 25-D's ability to temper bacterial-induced inflammation by slowing VDR activity. While this results in short-term palliation, persistent pathogens that may influence disease progression, proliferate over the long-term.

After much consideration into this blog's new name in the light of my new direction, the decision has been made. "Free the Animal" Why? First, if you read that post linked above, you know that my health and fitness approach is perfectly in harmony with my philosophical approach; and hence, my approach to politics and all that. In other words, a big part of the reason I have discovered something that truly works; and moreover, is the simplest, most natural, downright fun way of living: that gets you lean and fit; gets you feeling and sleeping great; and gets you looking years and years younger is precisely because I don't believe in the gods of heaven or earth, we evolved over millions of years and are conditioned by survival pressures that in no way include all vegetable diets, gorging on bottled water all day, eating ground grass seeds (grains and derivatives) running on a treadmill or elliptical, or involving ourselves in social schemes and cons that leave us powerless, with no influence, and at the mercy of the crowd and collective (the cannibal pot). Some have a lot of the pieces and do good work. I have all of the major pieces, though acquiring all of the specifics is a lifelong and never-ending journey of discovery. I will focus on essentials and specifics that really matter to me and others living a normal life in pursuit of survival, prosperity and happiness. I will point to other sources that provide more depth in specific areas that are of interest to only some