Taking a daily multivitamin supplement can slow age-related memory decline, finds a large study led by researchers at Columbia University and Brigham and Women's Hospital/Harvard.

"Cognitive aging is a top health concern for older adults, and this study suggests that there may be a simple, inexpensive way to help older adults slow down memory decline," says study leader Adam M. Brickman, PhD, professor of neuropsychology at Columbia University Vagelos College of Physicians and Surgeons.

Many older people take vitamins or dietary supplements under the assumption that they will help maintain general health. But studies that have tested whether they improve memory and brain function have been mixed, and very few large-scale, randomized trials have been done.

Study methods

In the current study, more than 3,500 adults (mostly non-Hispanic white) over age 60 were randomly assigned to take a daily multivitamin supplement or placebo for three years. At the end of each year, participants performed a series of online cognitive assessments at home designed to test memory function of the hippocampus, an area of the brain that is affected by normal aging. The COSMOS-Web study is part of a large clinical trial led by Brigham & Women's Hospital and Harvard called the COcoa Supplement and Multivitamin Outcomes Study (COSMOS).

By the end of the first year, memory improved for people taking a daily multivitamin, compared with those taking a placebo. The researchers estimate the improvement, which was sustained over the three-year study period, was equivalent to about three years of age-related memory decline. The effect was more pronounced in participants with underlying cardiovascular disease.

The results of the new study are consistent with another recent COSMOS study of more than 2,200 older adults that found that taking a daily multivitamin improved overall cognition, memory recall, and attention,  effects that were also more pronounced in those with underlying cardiovascular disease.

"There is evidence that people with cardiovascular disease may have lower micronutrient levels that multivitamins may correct, but we don't really know right now why the effect is stronger in this group," says Brickman.

Good nutrition important for aging brain

Though the researchers did not look at whether any specific component of the multivitamin supplement was linked to the improvement in memory, the findings support growing evidence that nutrition is important for optimizing brain health as we age.

"Our study shows that the aging brain may be more sensitive to nutrition than we realized, though it may not be so important to find out which specific nutrient helps slow age-related cognitive decline," says Lok-Kin Yeung, PhD, a postdoctoral researcher in Columbia's Taub Institute for Research on Alzheimer's Disease and the Aging Brain and first author of the study.

"The finding that a daily multivitamin improved memory in two separate cognition studies in the COSMOS randomized trial is remarkable, suggesting that multivitamin supplementation holds promise as a safe, accessible, and affordable approach to protecting cognitive health in older adults," says co-author JoAnn Manson, MD, chief of the Division of Preventive Medicine at Brigham and Women's Hospital.

"Supplementation of any kind shouldn't take the place of more holistic ways of getting the same micronutrients," adds Brickman. "Though multivitamins are generally safe, people should always consult a physician before taking them."