Vitamin E Pills May Boost Risk of Prostate Cancer Threat heightened even after men quit supplement, says study By Matt Cantor, Newser User Posted Oct 11, 2011 5:30 PM CDT 6 comments Comments Vitamin E tablets may increase the risk of prostate cancer. (Shutterstock) (Newser) – Supplements we take for better health may actually be hurting us. Yesterday we learned that vitamins may carry an increased risk of death for women; today's culprit is vitamin E, which may heighten the risk of prostate cancer. A study found that men who took the popular supplements faced a higher cancer risk even after ditching them, USA Today reports. Researchers studied a group of 35,000 men 50 and older. The subjects took the supplements—or placebos—for an average of five and a half years, stopping in 2008. As of this July, there were 17% more cases of prostate cancer in the men who took vitamin E than in the men who didn't. And 91 cases of cancer developed after the men had quit taking the vitamins. The authors aren't yet able to explain the results. "We don't really understand what the optimal levels of most of the vitamins are," says one. Click to read about a shift in attitude about prostate screening.