Multivitamins and cancer

Multivitamins and cancer

Observational studies have not shown a consistent decrease in cancer risk with multivitamin use.

• A large randomized trial of multivitamins, involving over 14,000 men has demonstrated a small, statistically-significant reduction in total cancer risk in the multivitamin group (1). The study included male physicians 50 years and older at recruitment. At a mean follow-up of 11.2 years, there was a reduction in total cancer from 18.3 to 17.0 events per 1000 person-years but there was no impact on cancer mortality.

• In the past a systematic review of 38 studies found that neither vitamin C nor vitamin E supplementation was beneficial for prevention of cancers (2).

• A 2006 NIH consensus concluded that “present evidence is insufficient to recommend either for or against the use of multivitamin supplements by the American public to prevent chronic disease” (3).
• A long-term randomized trial in women found no evidence that supplementation with vitamin C, E, or beta-carotene decreased cancer incidence or mortality (4).

• Two long term observational studies found no association between multivitamin use and risk of cancer. (5,6)

Currently it has not been established that multivitamin and mineral supplements provide added benefit to a balanced, healthful diet for most individuals.

References

1. Gaziano JM, Sesso HD, Christen WG, et al. Multivitamins in the prevention of cancer in men: the Physicians’ Health Study II randomized controlled trial. JAMA 2012;308:1871.
2. Coulter ID, Hardy ML, Morton SC, et al. Antioxidants vitamin C and vitamin e for the prevention and treatment of cancer. J Gen Intern Med 2006;21:735.
3. NIH State-of-the-Science Panel. National Institutes of Health State-of-the-science conference statement: multivitamin/mineral supplements and chronic disease prevention. Ann Intern Med 2006; 145:364.
4. Lin J, Cook NR, Albert C, et al. Vitamins C and E and beta carotene supplementation and cancer risk: a randomized controlled trial. J Natl Cancer Inst 2009;101:14.
5. Neuhouser ML, Wassertheil-Smoller S, Thomson C, et al. Multivitamin use and risk of cancer and cardiovascular disease in the Women’s Health Initiative cohorts. Arch Intern Med 2009;169:294.
6. Park SY, Murphy SP, Wilkens LR, et al. Multivitamin use and the risk of mortality and cancer incidence: the multiethnic cohort study. Am J Epidemiol 2011;173:906.