“Multivitamins basically prevented three years of age-related memory loss,” says a co-leader of the study, JoAnn Manson, MD, MPH, the chief of the division of preventive medicine at Brigham and Women’s Hospital, and a professor of medicine at Harvard Medical School in Boston. “Multivitamins are a safe, accessible, and affordable approach to protecting cognitive health,” Dr. Manson says.
Multivitamins Are No Substitute for Healthy Diet and Exercise
Manson emphasizes, however, that multivitamins are no substitute for a healthy diet and healthy lifestyle factors like regular exercise. She views the multivitamin as having a potentially complementary role — where it can especially help those who have some dietary inadequacies.
“We’re not recommending that you just throw multivitamins at a fast food diet full of processed and fried foods,” she says. “Our first recommendation is that you should try to improve your diet and not just start popping pills.”
Findings Suggest Benefit Regardless of Current Eating Habits
For the 2023 analysis, the study authors followed 3,562 older adults who were randomly divided into two groups: one assigned to a daily multivitamin supplement — the study used the Centrum Silver brand — and the other given a daily placebo. The average age was 71, about one-third were men, and just over 93 percent were white.
Because a statistically significant benefit was seen across the entire study population, the results suggest that even those who were eating a healthy diet were getting some benefit from taking multivitamin, according to Manson.
While details on vitamin and micronutrient deficiencies were not measured, scientists collected blood samples from a large percentage of the study population, and research into baseline nutritional status along with some baseline biomarkers of inflammation, cholesterol, and blood sugar, among others, is underway.
Although Centrum Silver was used in the study, Manson believes any high-quality, standard multivitamin is likely to provide these memory and cognitive benefits.
Study authors noted that those who had a prior history of cardiovascular disease (under 5 percent of the study population) did better with the multivitamins in terms of cognitive improvement. As to why this is the case, more extensive investigation is needed, according to the researchers.
How Researchers Measured Memory Gain
Those enrolled in the study completed self-administered, web-based assessments of memory and cognition annually over three years. For example, a test for memory recall required participants to view a list of 20 words and then type in all the words they remembered. For those in the vitamin group, performance improved on average from 7.10 words at study start to 7.81 words at one year — an increase of 0.71 words.
The average in the placebo group was 7.21 at study start, and improved by 0.44 to 7.65 after one year.
This effect of vitamin supplementation on memory was sustained over three years. While the effect was “significant,” the authors recognized that it was also small and may not be noticeable to all individuals taking vitamins — adding that “even small effect sizes can result in large health benefits at the population level.”
Not All Experts Are on Board With Multivitamin for Memory
Jeffrey Linder, MD, MPH, the chief of general internal medicine at the Northwestern Feinberg School of Medicine in Chicago, calls the results “intriguing,” but he did not find them “practice-changing.”
“They found a slight difference in immediate memory recall at year one, but not in years two or three,” says Dr. Linder, who was not involved in the research. “I have a hard time telling patients they should take a multivitamin to improve their word recall one year later — by about one-quarter of a word over the placebo group — and then there being no differences in years two and three.”
Vitamin takers in this study also performed no better in tests of their longer-term memory, visual memory, or executive function — mental abilities that allow us to plan, focus attention, remember, and juggle multiple tasks.
“I worry that people are substituting a multivitamin in place of a good diet or as an insurance policy against a bad diet,” says Linder. “I worry that all the focus on supplements and vitamins distract people from things that really keep us healthy, like exercise and eating a healthy, well-balanced diet with lots of fruits and vegetables.”
Linder adds that for those who follow healthy practices, vitamin deficiencies are rare.
More Data Is Needed to Determine Multivitamin Benefits for Different Groups
Still, Linder sees no harm in taking a daily multivitamin and would like to see longer-term randomized controlled trials assessing various measures of cognition reported.
Manson and her colleagues plan to do more extensive research on this topic, investigating if benefits are greater for those with lower nutritional status and lower socioeconomic status, and if younger groups of people experience mental gains from multivitamins. Adam Brickman, PhD, a professor of neuropsychology at Columbia and a coauthor with Manson, says the research team is in the process of preparing a grant application to address this exact question, though it would be several years before any study results are available.
“We now have separate trials showing benefits for memory and cognition with the multivitamins compared to placebo,” says Manson. “We know that nutrition is important for brain health, and this is such a clear signal of benefit.”
The Takeaway
For adults 60 and up, a daily multivitamin might prevent memory decline that would occur without the supplement. In a large study population, people taking a multivitamin performed better on memory tests than those who took a placebo pill. Multivitamin use has also been linked to the slowing of cognitive aging and improvement in episodic memory. While the positive effects were seen across the study population — meaning that even people with a healthy diet were getting a benefit, as well as those who may be lacking in certain nutrients — remember that multivitamins are not a substitute for healthy eating and regular exercise.
Additional reporting by Deborah Shapiro.
