Work

Response: Re: Multivitamin Use and Risk of Prostate Cancer in the National Institutes of Health AARP Diet and Health Study

Year: 2007

Type: article

Abstract: Hickey et al. suggest that our results have limited public health relevance. However, we observed a substantial increase in risk for fatal prostate cancer (relative risk = 1.98; 95% confidence interval = 1.07 to 3.66) among men reporting excessive use of multivitamins ( 1 ). If, as in our study, 5% of men older than age 50 take multivitamins more than once a day, then, in light of the large number of prostate cancer–related deaths in the United States ( 2 ), our findings have potentially important consequences for public health. With respect to multiple testing of subgroups, our results section did include a list of the total number of nutrients and foods tested. In addition, our discussion section noted the possibility of chance findings due to multiple comparisons. We did not evaluate vitamin C because there is no a priori hypothesis linking vitamin C to prostate cancer risk. In contrast, we did examine vitamin E and its isoforms in detail in a separate recent publication ( 3 ) because vitamin E holds promise for prostate cancer prevention. Our study was not designed to address the effect of pharmacologic doses of nutrients on cancer prognosis or survival. We did, however, find strong epidemiologic evidence against a protective effect of excessive use of multivitamins on prostate carcinogenesis. The conclusion that people should use natural antioxidant supplements and avoid synthetic forms does not follow from our study. Our study did not compare the effect of natural versus synthetic ingredients contained in multivitamin supplements.

Source: JNCI Journal of the National Cancer Institute

DOI: 10.1093/jnci/djm139

Authors: K. A. Lawson, M. E. Wright, T. Mouw, A. Hollenbeck, A. Schatzkin, M. F. Leitzmann