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Americans spend billions of dollars on supplements each year, and about one in three adults report taking a multivitamin. But there is some debate about whether it helps promote good health.
A team of researchers wanted to assess how a daily multivitamin can influence cognitive aging and memory. They followed about 3,500 older people enrolled in a randomized controlled trial. One group of participants took a placebo and another group took a Silver Centrum multivitamin for 3 years. Participants also took tests, administered online, to assess memory.
By the end of the first year, people taking a multivitamin showed improvements in the ability to remember words. Participants were given lists of words, some related, some not, and asked to remember as many of them as possible. (List learning tests assess a person’s ability to store and retrieve information.)
People taking the multivitamin were able to remember about a quarter more words, which translates to memorizing a few more words, compared to the placebo group.
“We estimate that the multivitamin intervention effect improved memory performance compared to placebo by the equivalent of 3.1 years of age-related memory change,” the authors write in their paper, published this week in the American Journal of Clinical Nutrition. And the authors point to a lasting benefit.
“It’s intriguing,” says Dr. Jeffrey Linder, chief of general internal medicine at Northwestern University Feinberg School of Medicine, who was not involved in the study. But he says the overall effect found in the study was quite small. “That seems like a pretty modest difference,” Linder says. And, he points out that the multivitamins had no effect on other areas of cognition assessed in the study such as executive function, which may be more important measures.
Study author Dr. JoAnn Manson, who is chief of the division of preventive medicine at Brigham and Women’s Hospital, says this isn’t the first study to show the benefits of multivitamins. She points to a study published last year in Alzheimer’s & Dementia that showed participants who took a daily multivitamin performed better, overall, on overall cognitive function, on tests measuring story recall , verbal fluency, digit order, and executive function.
“It’s surprising that such a clear signal for benefit in slowing age-related memory loss and cognitive decline was found in the study,” Manson says. “Those who received the multivitamin did better than those who received the placebo.”
Our body and brain need many nutrients for optimal health and efficiency. Manson says that if people have deficiencies in these nutrients, it can influence memory loss or hasten cognitive decline. So, she says, taking a multivitamin can help someone prevent a deficiency, if they’re not getting all the nutrients they need from their diet.
“It’s important to emphasize that a multivitamin will never replace a healthy diet,” Manson says, because micronutrients are generally better absorbed from food than from supplements. “But it may be a complementary approach or strategy to maintaining cognitive health in older adults,” she says.
Linder says he will continue to tell his patients that if they eat a healthy diet, they are unlikely to benefit much from a multivitamin. “If you take too much of a particular supplement and your body doesn’t need it, you just pee it,” he says. He wrote an op-ed, published in JAMA, claiming that vitamins and supplements could be a waste of money for many people. He argues that we should help people eat better.
“A diet rich in fruits and vegetables is associated with longevity, better function and improved quality of life,” says Linder. Plenty of research shows that a healthy diet is linked to better heart health, and when it comes to protecting cognitive function, “current thinking is that whatever is good for your heart is also good for your brain. “, he says. .
When Linder talks to his patients about healthy aging, he focuses on good sleep habits, physical activity, and healthy eating. “My big concern with all the attention people are giving to vitamins is that it distracts them from things that will actually help them stay healthy,” Linder says.
“If someone is on a multivitamin, I’m not going to tell them to stop,” says Dr. R. Sean Morrison, who is a geriatrician at Mt. Sinai Health System in New York. But he says he wouldn’t encourage the use of multivitamins as a means of protecting against memory loss because he says the effects measured in studies aren’t very compelling. “I don’t think that’s the magic formula people are looking for,” Morrison says. When he talks to his patients, he too emphasizes the importance of healthy habits and good social relationships.
The study was funded, in part, by the National Institutes of Health and other grants. The vitamins were provided by Pfizer, Inc. and Haleon, makers of Centrum, the brand of multivitamins taken by study participants. The study authors say the funders had “no role” in the design, analysis or interpretation of the study.