A large number of Americans take multivitamins in hopes of improving their health but three new studies, all released in the Annals of Internal Medicine on the same day, suggest these dietary supplements may not be helpful. In some cases, multivitamin use may even be harmful.
The first study looked at whether long-term use of multivitamins improves cognitive health later in life. Researchers in this study enrolled 5947 male physicians aged 65 and older in a double-blind study between 1997 and 2011; some participants took multivitamins while others received a placebo. Researchers conducted telephone interviews to assess the participants’ cognitive function and found no difference between the two groups.
Researchers in the next study hoped to determine whether multivitamins can reduce the risk for heart problems and if oral supplements are safe for that use. These scientists looked at 1708 patients age 50 or older who had suffered a heart attack at least six weeks prior to the study. The researchers randomly assigned participants to either a multivitamin group or a placebo group. After about three years, the scientists did not see any statistically significant reduction in the recurrence of heart problems among those in the vitamin group.
The third study investigated the claim that multivitamin use prevents chronic disease, especially cardiovascular disease and cancer. These researchers found vitamins did not provide any benefit in the prevention of chronic diseases.
An editorial entitled, “Enough Is Enough: Stop Wasting Money on Vitamin and Mineral Supplements” accompanied the three studies. The authors of the editorial point out that use of vitamins have increased from 30 percent in 1994 to 39 percent between 2003 and 2006, while mineral supplement use increased from 42 percent to 52 percent in those years, despite any clear evidence that these dietary supplements work. Americans now spend $28 billion annually on vitamin and mineral supplements.
Vitamin supplements are helpful for those suffering deficiencies resulting from medical problems or abject poverty, which are rare in the United States where better nutrition and education have eradicated severe hunger. Taking too many vitamins can cause cancer, liver damage, coma, and even death.
- Grodstein, Francine, ScD, et al. "Long-Term Multivitamin Supplementation and Cognitive Function in Men: A Randomized Trial." Annals of Internal Medicine. N.p., 17 Dec. 2013. Web. 30 Dec. 2013.
- Lamas, Gervasio A., MD, et al. "Oral High-Dose Multivitamins and Minerals After Myocardial Infarction: A Randomized Trial." Annals of Internal Medicine. N.p., 17 Dec. 2013. Web. 30 Dec. 2013.
- Fortmann, Stephen P. MD, et al. "Vitamin and Mineral Supplements in the Primary Prevention of Cardiovascular Disease and Cancer: An Updated Systematic Evidence Review for the U.S. Preventive Services Task Force FREE." Annals of Internal Medicine. N.p., 13 Dec. 2013. Web. 30 Dec. 2013.
- Guallar, Eliseo MD, DrPH, et al. "Enough Is Enough: Stop Wasting Money on Vitamin and Mineral Supplements FREE." Annals of Internal Medicine. N.p., 13 Dec. 2013. Web. 30 Dec. 2013.