The role of Vitamin D in biologic functions other than the maintenance of bone health is an area of intense research interest. The latest chapter to be written is in the May 9, 2014 issue of Clinical Cancer Research. From a consortium of hospitals in Chicago, urologists measured vitamin D levels in all men about to undergo prostate biopsy for a suspicion of cancer. They found that men with the lowest vitamin D levels had the highest risk of having an aggressive prostate cancer. This tendency was seen most prominently in African American men, who tend to get prostate cancer at an earlier age and do worse with it anyway. Because the study was done in Chicago, average vitamin D levels across the board were low, and some men had extremely low levels.
Other data suggest that taking men with early prostate cancer who elect not to be treated, and loading them with vitamin D can reverse the malignant changes seen on the original prostate biopsy when subsequent sample is taken.
How does this fit in? A review article by Vuolo et al in Frontiers in Endocrinology puts this observation in perspective. The authors review the preclinical and clinical data on the role of vitamin D as a cancer preventative. Makes great reading if you can immerse yourself in the details. Dr. Stark can send you the full text of both of these articles if requested. He cannot post links to the full articles on this site because of copyright protection.
Dr. Stark comments, “These observations are very good news. They provide a basis for a non-toxic evidence-based approach to cancer prevention. We now have one more reason not to be deficient in vitamin D.”
Update 2020: the observation of vitamin D levels and prognosis has been extended to melanoma in the same way. With colon cancer, the risk of getting the disease is inversely related to vitamin D levels in women. Why only women is not clear, but vitamin D is related structurally to sex hormones. Finally some authors believe that vitamin D can prevent cancer across a wide variety of tumor types.