Vitamin D Deficiency Linked to Prostate Cancer
In winter and spring, plasma levels of vitamin D insufficient in 36 to 77 percent of men
THURSDAY, March 22 (HealthDay News) -- Men in the United States often have insufficient plasma levels of vitamin D and those with lower levels have a higher risk of prostate cancer, particularly if they also have a polymorphism that results in a less functional vitamin D receptor, according to a study in the March issue of PLoS Medicine.
Haojie Li, M.D., of Brigham and Women's Hospital and Harvard Medical School in Boston, and colleagues studied 14,916 men enrolled in the Physicians' Health Study who were initially cancer-free. After 18 years of follow-up, they identified 1,066 subjects with incident prostate cancer and compared their vitamin D status with that of 1,618 cancer-free, age- and smoking-matched controls.
The researchers found that men with below-median levels of vitamin D had a significantly higher risk of aggressive prostate cancer than men with above-median levels (odds ratio, 2.1). Men with below-median levels of vitamin D and the vitamin D receptor polymorphism FokI ff had a higher risk of total and aggressive prostate cancer than those with above-median levels and the Ff or FF genotype (odds ratios, 1.9 and 2.5, respectively).
Overall, 13 to 51 percent of the physicians in the study were vitamin D deficient in the summer/fall and 36 to 77 percent were deficient in the winter/spring. "Vitamin D insufficiency is a common problem, and improving vitamin D status through moderate sun exposure and vitamin D supplements, in particular, is essential for optimal health," the authors conclude.