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Americans spend billions of dollars on supplements every year, and roughly Report 1 in 3 adults take a multivitamin. But there is debate as to whether this helps promote good health.
A team of researchers wanted to evaluate how a daily multivitamin can affect cognitive aging and memory. They monitored approximately 3,500 older adults who were enrolled in a randomized controlled trial. One group of participants took a placebo and another group took a Silver Center multivitamin, for three years. Participants also took tests, administered online, to assess memory.
At the end of the first year, people taking 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 evaluate 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 remembering just a few more words, compared to the placebo group.
« We estimate that the effect of the multivitamin intervention improved memory performance versus placebo by the equivalent of 3.1 years of age-related memory change, » the authors write in their paper, which was published this week on American Journal of Clinical Nutrition. And the authors point to a lasting 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 she says the overall effect found in the study was quite small. « It seems like a pretty modest difference, » Linder says. And she points out that the multivitamins had no effect on other cognitive areas 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. Indicate a study published last year in Alzheimer’s and dementia which showed that participants who took a daily multivitamin performed better, overall, on global cognitive function on tests measuring story recall, verbal fluency, digit ordering, and executive function.
« It’s surprising that such a clear signal of benefit in slowing age-related memory loss and cognitive decline was found in the study, » says Manson. « 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, it can affect memory loss or accelerate cognitive decline. So, he says taking a multivitamin can help someone prevent a deficiency if he’s not getting all the nutrients he needs from his diet.
« Importantly, a multivitamin will never replace a healthy diet, » says Manson, since micronutrients are typically better absorbed through food than through supplements. « But it could be a complementary approach or strategy for maintaining cognitive health among 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’re taking too much of a particular supplement and your body doesn’t need it, you’re just making it pee, » she says. She 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, improved function, and a better quality of life, » Linder says. There is a lot of research showing that a healthy diet is linked to better heart health, and when it comes to protecting cognitive function, « the current view is that all the things that are good for the heart are also good for the brain » she says. .
When Linder talks to his patients about healthy aging, he focuses on good sleep habits, physical activity and a healthy diet. « My big concern with all the attention people have on vitamins is that it’s distracting them from things that will actually help them stay healthy, » Linder says.
« If someone is taking a multivitamin, I’m not going to tell them to stop, » she says Dr. R. Sean Morrison, geriatrician at Mount Sinai Health System in New York. But he says he wouldn’t encourage the use of multivitamins as a way to protect against memory loss, because he 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, » says Morrison. When he talks to his patients, he too 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 multivitamins taken by study participants. The study authors say the funders had « no role » in the design, analysis or interpretation of the study.