Vitamin D

True to form, Dr. John Cannell has published yet another wonderfully insightful Vitamin D Newsletter. One item caught my eye, a response to a question about the Marshall Protocol. I, like Dr. Cannell, was inundated with questions about this so-called protocol, which amounts to little more than the unfounded speculations of a non-physician, actually someone not even involved in health care. In all honesty, I blew the whole issue off after I read Dr. Marshall's rants. They smack of pure quackery, though from somebody who clearly has a command of scientific lingo. To Dr. Cannell's credit, he took the time and effort to construct a rational response in the latest issue of the newsletter. I reproduce his response here:

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

Low vitamin D status despite abundant sun exposure. Binkley N, Novotny R, Krueger D, Kawahara T, Daida YG, Lensmeyer G, Hollis BW, Drezner MK. J Clin Endocrinol Metab. 2007 Jun;92(6):2130-5. Epub 2007 Apr 10. PMID: 17426097 doi:10.1210/jc.2006-2250 CONCLUSIONS: These data suggest that variable responsiveness to UVB radiation is evident among individuals, causing some to have low vitamin D status despite abundant sun exposure. In addition, because the maximal 25(OH)D concentration produced by natural UV exposure appears to be approximately 60 ng/ml, it seems prudent to use this value as an upper limit when prescribing vitamin D supplementation.

According to a study conducted by University of Wisconsin researchers, even people who are regularly exposed to sunlight can have low vitamin D levels. The study focused on subjects who lived in sunny Hawaii and spent an average of 11.1 hours in the sun each week. (None of the participants in the study used any type of sunscreen.) Despite the exposure, 51 percent of participants were found to be deficient in vitamin D.

Vitamin D supplementation enhances the beneficial effects of weight loss on cardiovascular disease risk markers. Zittermann A, Frisch S, Berthold HK, Götting C, Kuhn J, Kleesiek K, Stehle P, Koertke H, Koerfer R. Am J Clin Nutr. 2009 May;89(5):1321-7. Epub 2009 Mar 25. PMID: 19321573

Current micronutrient recommendations in Europe: towards understanding their differences and similarities. Doets EL, de Wit LS, Dhonukshe-Rutten RA, Cavelaars AE, Raats MM, Timotijevic L, Brzozowska A, Wijnhoven TM, Pavlovic M, Totland TH, Andersen LF, Ruprich J, Pijls LT, Ashwell M, Lambert JP, van 't Veer P, de Groot LC. Eur J Nutr. 2008 Apr;47 Suppl 1:17-40. PMID: 18427858 DOI: 10.1007/s00394-008-1003-5 Full text: http://www.eurreca.org/downloadattachment/3199/1535/ejn%201003ov.pdf

The review, published in Osteoporosis International, provides a global perspective of vitamin D status across different regions of the world and identifies common and significant determinants of hypovitaminosis D. Six regions of the world were reviewed-Asia, Europe, Middle East and Africa, Latin America, North America, and Oceania-through a survey of published literature.

Global vitamin D status and determinants of hypovitaminosis D. Mithal A, Wahl DA, Bonjour JP, Burckhardt P, Dawson-Hughes B, Eisman JA, El-Hajj Fuleihan G, Josse RG, Lips P, Morales-Torres J; on behalf of the IOF Committee of Scientific Advisors (CSA) Nutrition Working Group. Osteoporos Int. 2009 Jun 19. [Epub ahead of print] PMID: 19543765 CONCLUSION: Reports from across the world indicate that hypovitaminosis D is widespread and is re-emerging as a major health problem globally.

Diagnosis and Treatment of Vitamin D Deficiency Seminar December 2, 2008

Diagnosis & Treatment of Vitamin D Deficiency Wednesday, April 9, 2008 * 12:30pm - 6:00pm Garren Auditorium, University of California, San Diego Seminar Presentations

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.

Current impediments to acceptance of the ultraviolet-B-vitamin D-cancer hypothesis. Grant WB, Boucher BJ. Anticancer Res. 2009 Sep;29(9):3597-604. PMID: 19667154 The ultraviolet-B (UVB)-vitamin D-cancer hypothesis was proposed in 1980. There have been numerous ecological, observational and other studies of the hypothesis. There are about 14 types of cancer for which it seems to apply: bladder, breast, colon, endometrial, esophageal, gallbladder, gastric, ovarian, pancreatic, rectal, renal and vulvar cancer and both Hodgkin's and non-Hodgkin's lymphoma. Nonetheless, the hypothesis has not yet been accepted by public health agencies. Some of the reasons for this include a distrust of ecological studies, some mistrust of observational studies, and the existence of just one positive randomized controlled trial, an analysis of a vitamin D and calcium supplementation study involving post-menopausal women in Nebraska. Paradigm shifts such as this generally take time, in part due to opposition from those content with the status quo. In this paper, results of ecological studies in the United States using summertime solar UVB as the index of vitamin D production, which is highly asymmetrical with respect to latitude, and indices for other cancer risk-modifying factors (air pollution, alcohol consumption, dietary iron and zinc, ethnic background, socioeconomic status, smoking and urban/rural residence) are discussed in terms of supporting the hypothesis. These studies were not considered while other ecological studies were examined in recent critiques of the hypothesis. While additional randomized controlled trials would, of course, be helpful, the current evidence seems to satisfy the criteria for causality as outlined by A. Bradford Hill.

Ecological studies of ultraviolet B, vitamin D and cancer since 2000. Grant WB, Mohr SB. Ann Epidemiol. 2009 Jul;19(7):446-54. Epub 2009 Mar 9. PMID: 19269856 CONCLUSION: These findings provide strong evidence that vitamin D status plays an important role in controlling the outcome of cancer. Support for the UVB-vitamin D-cancer theory is now scientifically strong enough to warrant use of vitamin D in cancer prevention, and as a component of treatment. More research studies would help to explore whether there are benefits beyond the substantial effects that have been observed.

Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. Lappe JM, Travers-Gustafson D, Davies KM, Recker RR, Heaney RP. Am J Clin Nutr. 2007 Jun;85(6):1586-91. Erratum in: Am J Clin Nutr. 2008 Mar;87(3):794. PMID: 17556697 Conclusions: Improving calcium and vitamin D nutritional status substantially reduces all-cancer risk in postmenopausal women.

Vitamin D supplementation. Eveleigh B. Can Fam Physician. 2007 Sep;53(9):1435; author reply 1435. PMID: 17872869 My concern regarding vitamin D2 is that it is a synthetic analogue and might interact with the vitamin D receptor differently in various cell systems. It has been reported that vitamin D3 might improve glycemic control.7 Vitamin D2 has been reported to cause worsening of glycemic control in people of East Indian descent.8 Is this because of vitamin D receptor polymorphism, or because of enhanced 24-hydroxylase enzyme activation, or is it due to how vitamin D2 interacts with the receptor? Until this has been sorted out, I feel safest using vitamin D3. There are about 2000 synthetic analogues of vitamin D. The search is on for one that can cross the blood-brain barrier to treat certain types of brain cancers without causing hypercalcemia.9 But then again, what other effects would this compound have? There are still so many unknowns

Not enough vitamin D: health consequences for Canadians. Schwalfenberg G. Can Fam Physician. 2007 May;53(5):841-54. Review PMID: 17872747 Conclusion Low levels of VTD are considered a major public health problem in Canada, especially during the winter. Those with risk factors should be screened for low 25(OH)D levels and repletion therapy instituted if needed. Researchers have estimated that the oral dose of vitamin D3 to attain and maintain 25(OH)D levels >80 nmol/L is 2200 IU/d if baseline levels are 20 to 40 nmol/L, 1800 IU/d if levels are 40 to 60 nmol/L, and 1160 IU/d if levels are between 60 and 80 nmol/L.64 We need to ensure that patients have healthy blood levels of 25(OH)D to prevent levels of parathyroid hormone from rising and to maximize absorption of calcium, magnesium, and phosphate. Positive effects on bone are marginal at best unless patients consume at least 800 IU/d of VTD. The emerging and exciting role of the VTD receptor and the actions of VTD in maintaining health in other cell types have become more apparent during the last decade.

This month, the authoritative International Agency for Research into Cancer (IARC) have weighed in on the issue. By gathering a group of expert scientists, they have looked at all the available evidence and published a detailed report on vitamin D and cancer. The massive tome weighs in at 465 pages, but we'll take a look at the key points in the first of two posts looking at the vitamin D debate. It is impossible for us to get more than about five percent of the vitamin D we need from our diet - unless, like Eskimos, we eat oily fish three times a day.

Why would vitamin D be prescribed when vitamin D3 is available over-the-counter? Let's review the known differences between vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol): --D3 is the human form; D2 is the non-human form found in plants. --Dose for dose, D3 is more effective at raising blood levels of 25-hydroxy vitamin D than D2. It requires roughly twice to 250% of the dose of D2 to match that of D3 (Trang H et al 1998). --D2 blood levels don't yield long-term sustained levels of 25-hydroxy vitamin D as does D3. When examined as a 28-day area under the curve (AUC--a superior measure of biologic exposure), D3 yields better than a 300% increased potency compared to D2. This means that it requires around 50,000 units D2 to match the effects of 15,000 units D3 (Armas LA et al 2004). --D2 has lower binding affinity for vitamin D-binding protein, compared to D3 --Mitochondrial vitamin D 25-hydroxylase converts D3 to the 25-hydroxylated form five times more rapidly than D2. --As we age, the ability to metabolize D2 is dramatically reduced, while D3 is not subject to this phenomenon

Higher levels of 25-hydroxyvitamin D are associated with a lower incidence of multiple sclerosis only in women. Kragt J, van Amerongen B, Killestein J, Dijkstra C, Uitdehaag B, Polman Ch, Lips P. Mult Scler. 2009 Jan;15(1):9-15. Epub 2008 Aug 13. PMID: 18701572 DOI: 10.1177/1352458508095920 CONCLUSIONS: Our data suggest that higher circulating levels of 25(OH)D are associated with a lower incidence of MS and MS-related disability in women. This may imply clues to the pathogenesis of the sex difference in risk and to the nature of the environmental factors involved in MS.

Vitamin D may suppress infections which lead to development of Multiple Sclerosis Steven R Brenner, None (16 August 2007) J Neurol Neurosurg Psychiatry 2008 I read the article with reference to the inverse relationship between multiple sclerosis clinical activity and deficiency of vitamin D by Soilu-Hannienen (1) with interest, and was considering what mechanism could be in play to cause such a relationship. 25-hydroxylated metabolites of vitamin D act as intracellular regulators of the synthesis and action of defensin (2) molecules against bacterial antigens, defensin being an endogenously synthesized antimicrobial substance (2). Human cathelicidin antimicrobial peptide gene is a target of vitamin D receptor and is strongly up-regulated by 1,25-dihydroxyvitamin D3, indicating vitamin D receptor and the 1,25-dihydroxyvitaminD3 regulate primate innate immunity (3)