An increasing number of men may be taking vitamins, but new data indicate that these supplements may not provide preventive effects against urothelial and prostate cancers. Research from two new studies will be presented during the 105th Annual Scientific Meeting of the American Urological Association (AUA) in San Francisco.

In the first study, researchers from the University of Colorado examined more than 10,000 questionnaires from men taking part in the Prostate Cancer Awareness Week (PCAW) screenings. Overall, 62 percent of respondents reported taking at least one supplement while 48 percent indicated they were currently taking three or more supplements. Researchers noted that supplement use increased significantly with age. Although multivitamins (46 percent) were the most commonly reported supplement, fish oil (27 percent) and vitamin C (26 percent) were also very popular. "The high prevalence of supplement use reported in this study is of potential concern," the authors note. "Previous studies suggest an association between multivitamin use and increased risk of advanced prostate cancer."

Researchers in Washington conducted a separate study of 77,719 state residents, aged 50-76 years old, who completed a questionnaire from 2000-2002, and were followed for the next five years through the Surveillance, Epidemiology, and End Results (SEER) cancer registry. Overall, 330 residents were found to have developed urothelial cell carcinoma of the bladder (UC). In a multivariate analysis, the researchers found that vitamin use provided no protective effect on UC.

"It's really disturbing to think that so many people are taking vitamins, assuming that these pills are providing some sort of health benefits," said session moderator Mark A. Moyad, MD. "The reality is that very little scientific research has proven vitamins to be effective in protecting against cancer and some studies have even shown that taking certain vitamins could increase one's risk of cancer."

Source
American Urological Association