LAUSR

Although multivitamins are among the most commonly used supplements in the U.S., their effectiveness in preventing cancer and other chronic diseases is unclear. To help address this uncertainty, we prospectively investigated the association between multivitamin use and risk of overall and site-specific cancer in 489,640 participants enrolled in the National Institutes of Health (NIH) - AARP Diet and Health Study. We defined site-specific cancers using the Surveillance Epidemiology and End Results (SEER) incidence and the International Classification of Diseases for Oncology coding (3rd ed.). Multivitamin use was assessed by questionnaire at baseline and categorized as never, 1 per day. Cox proportional hazards regression models of multivitamin use estimated hazard ratios (HRs) and 95% confidence intervals (CIs) that adjusted for multiple potential confounders including gender, age, body mass index, smoking status, and Healthy Eating Index-2015 (HEI-2015) score. We observed no association between increasing multivitamin use and overall cancer risk (HRs 1.0 (reference, never use) 0.94, 0.96, 1.01, 1.00; trend P-value=0.42). Multivitamin use was, however, inversely associated with colon cancer risk: HR=0.79, 95% CI=0.70-0.89 (trend P-value 1 multivitamin daily compared with never users, a finding that was identical in men and women (HR=0.79, 95% CI=0.68-0.92 and HR=0.79, 95% CI=0.65-0.95, respectively). Although there were some additional suggestive findings (e.g., for oropharyngeal cancer and leukemia), multivitamin use was not associated with the risk of cancer of the breast, prostate, or lung. In this study that comprehensively evaluated multivitamin use in relation to the risk of overall and site-specific malignancies in both men and women, we found little evidence to support beneficial associations, with the exception of colon cancer risk in both sexes. Citation Format: Jungeun Lim, Stephanie J. Weinstein, Linda M. Liao, Jiaqi Huang, Demetrius Albanes. Multivitamin use and risk of overall and site-specific cancer in the National Institutes of Health - AARP Diet and Health Study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 850.