Mega Multivitamins and Prostate Cancer

Men who take too many multivitamins may be increasing their risk of dying from prostate cancer, according to new research from the National Cancer Institute.

Taking a multivitamin more than seven times a week was associated with a 30% increased risk of advanced prostate cancer and a doubling of the risk of death from the disease in the study.

Regular multivitamin use (one to six times a week) did not appear to increase cancer risk, and excessive vitamin use was not associated with an increased risk of early, or localized, prostate cancer.

But there was also no evidence to suggest that taking multivitamins at any dosage helped prevent prostate cancer.

NCI researcher Michael F. Leitzmann, MD, PhD, tells WebMD that more research is needed to confirm the association and understand how vitamin and other dietary supplements affect cancer risk.

“Based on our findings, we would recommend that men adhere to recommendations for dietary supplements and consult with their physician before taking supplements in excessive doses,” he says.