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Americans spend billions of dollars on supplements each year and approximately one in three adults reports taking a multivitamin. But there is debate about whether this helps promote good health.
A team of researchers wanted to test how a daily multivitamin might influence cognitive aging and memory. They followed about 3,500 older adults who enrolled in a randomized controlled trial. One group of participants took a placebo and another group took a silver center multivitamin, for 3 years. The participants also took tests, administered online, to assess memory.
By the end of the first year, people who took a multivitamin showed improvements in their ability to remember words. Participants were given lists of words, some related, some not, and asked to recall as many as possible. (List learning tests assess a person’s ability to store and retrieve information.)
People who took the multivitamin were able to remember about a quarter more words, which translates to remembering just a few more words, compared to the placebo group.
“We calculated that the effect of the multivitamin intervention improved memory performance over placebo by the equivalent of 3.1 years of age-related changes in memory,” the authors write in their paper, which was published this week in the American Journal of Clinical Nutrition. And the authors point to a sustained benefit.
“This is intriguing,” he 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. “It seems like a pretty modest difference,” says Linder. And she points out that the multivitamins had no effect on other areas of cognition tested 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 studio. published last year in Alzheimer’s & Dementia which showed that participants who took a daily multivitamin performed better overall in global cognitive function, on tests measuring story recall, verbal fluency, digit ordering, as well as executive function.
“It is surprising that the study found such a clear sign of benefit in slowing age-related memory loss and cognitive decline,” Manson says. “Those who received the multivitamin did better than those who received the placebo.”
Our bodies and brains require many nutrients for optimal health and efficiency. Manson says that if people are deficient in these nutrients, they can influence memory loss or accelerate cognitive decline. So, he says, taking a multivitamin can help someone prevent a deficiency if they don’t get all the nutrients they need from their diet.
“It’s important to stress that a multivitamin will never be a substitute for a healthy diet,” says Manson, as micronutrients are generally better absorbed through food than through supplementation. “Adults,” he 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’re taking too much of a particular supplement and your body doesn’t need it, you’re just urinating it out,” she says. He wrote an editorial, published in JAMA, arguing that vitamins and supplements could be a waste of money for many people. He argues that we should help people adopt a better eating pattern.
“Eating a diet rich in fruits and vegetables is associated with longevity and better function and better quality of life,” says Linder. There’s plenty of research showing that a healthy diet is linked to better heart health, and when it comes to protecting cognitive function, “the current thinking is that whatever’s good for your heart is also good for your brain.” she says. .
When Linder talks to her patients about healthy aging, she focuses on good sleep habits, physical activity, and a healthy diet. “My big concern with all the focus people have on vitamins is that it distracts them from the things that will really help them stay healthy,” she says.
“If someone is taking a multivitamin, I’m not going to tell them to stop,” she says. Dr. R. Sean Morrison, who is a geriatrician at Mt. Sinai Health System in New York. But she says she wouldn’t recommend using multivitamins as a way to protect against memory loss, because she says the effects measured in the studies aren’t very convincing. “I don’t think it’s the magic bullet that people are looking for,” Morrison says. When talking to his patients, he also focuses on 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, the makers of Centrum, the brand of multivitamin the study participants took. The study authors say the funders “had no role” in the design, analysis or interpretation of the study.