The longitudinal study followed 14,641 male doctors over the age of 50 for an average of 11.2 years. The doctors were randomly placed into two groups—a multivitamin-receiving group and a placebo group. The individuals who took the multivitamin for the 11-year period were eight percent less likely to develop any type of cancer than their counterparts who were given the placebo.
Of the 14,641 subjects, 2,669 of them were diagnosed with cancer during the study. A whopping nearly 50 percent of those diagnosed were determined to have prostate cancer. These results, however, could be a product of the popularity of PSA (prostate-specific atigen) screening tests at the time of the study. The researchers added that most of the time prostate cancers are benign and that the use of a daily multivitamin could help lower the risk of more malicious cancers beyond the eight percent rate of the study.