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Vitamin D and breast cancer. Bertone-Johnson ER. Ann Epidemiol. 2009 Jul;19(7):462-7. Epub 2009 Feb 20. Review. PMID: 19230714 Though the relationship between vitamin D and breast cancer remains unclear, a growing body of evidence suggests that vitamin D may modestly reduce risk. A large number of in vitro studies indicate that vitamin D can inhibit cell proliferation and promote apoptosis and cell differentiation in breast tumor tissue. Results from analytic studies of sunlight exposure and dietary intake have been inconsistent but together generally support a modestly protective role of vitamin D, at least in some population subgroups. Studies using blood vitamin D metabolites to assess vitamin D status may be less prone to misclassification than those of diet and sunlight exposure. Overall, the two prospective and four case-control studies of 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D tend to support a protective effect in older women. The relationship between common vitamin D receptor polymorphisms and risk remains unclear. Many questions about this relationship clearly remain, including the utility of assessing vitamin D through diet and sunlight exposure, the relationship between plasma metabolites, and the potential modifying effects of age, menopausal status and tumor characteristics. Given that vitamin D status is modifiable, additional prospective studies are necessary to determine if vitamin D may have important potential for breast cancer prevention.

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.

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.

What causes coronary heart disease or coronary atherosclerotic plaque, this thing that we track with heart scans? Well, here are a few little-publicized facts about heart disease that you are unlikely to hear from your When's-the-next-stent? cardiologist or the What is there besides statins? primary care doctor. (Since everybody knows that smoking is a modifiable risk for heart disease that can be readily identified, let's focus on the blood tests that reveal heart disease causes.)

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.

M. F. McCarty and K. I. Block Toward a core nutraceutical program for cancer management. Integr Cancer Ther, June 1, 2006; 5(2): 150 - 171.