Scientists at Northwestern University’s Feinberg School of Medicine have established a link between the risk of prostate cancer and vitamin D deficiency. Per the article:
600 men between the ages of 40-79, with elevated prostate-specific antigen, from the Chicago area, were studied. Each man was individually screened for vitamin D deficiency and then underwent a prostate biopsy. What the researchers found was that the men with the deficiency seemed to have a much higher chance of developing prostate tumors in the future.
Men with darker skin had a higher risk of developing prostate cancer possibly because sunlight penetrating the skin is a source of vitamin D and darker skinned men tend to have less sunlight penetration of the skin.
Thanks for the research, John.