Daily multivitamin consumption can improve memory – 02/04/2024 – Balance and Health

A new study reported that adults ages 60 and older who took a multivitamin daily for two years had higher scores on tests of memory and cognition than those who took a placebo — a rare example of a clinical trial that found that a nutritional supplement can actually benefit healthy people.

“This suggests that multivitamins may be a safe and affordable approach to protecting cognitive health in older adults,” said Chirag Vyas, a psychiatric epidemiologist at Mass General Brigham in Boston and one of the lead authors of the study, published May 18 in The American Journal of Clinical Nutrition.

But experts not involved in the trial warned that the benefits were small and it was unclear whether they would bring noticeable improvements to people’s lives.

“I would put it in the promise realm,” said Mary Butler, an associate professor of public health at the University of Minnesota who has published several papers evaluating interventions to prevent dementia.

The research was part of a larger study involving more than 21,000 older adults that looked at whether supplements can protect against various age-related diseases, called the Cocoa Supplement and Multivitamin Outcomes Study (Cosmos). The new report included results from a subset of 573 participants — mostly white and relatively well-educated — who took various cognitive tests in person.

People in the multivitamin and placebo groups improved their cognitive scores over two years, possibly because they were already familiar with the tests. But participants taking the multivitamin showed slightly greater gains, with the biggest increase occurring in memory assessments.

The study also grouped these findings with the results of two previous Cosmos investigations that tested the cognition of more than 5,000 people over the phone or online. In all three studies, those who took multivitamins had a consistent improvement in their scores on tests of memory and general cognitive ability compared with people who received a placebo, said JoAnn Manson, a professor of medicine at Harvard University and the trial’s co-principal investigator.

The researchers estimated that the memory boost seen in people taking the multivitamin corresponded to a two-year reduction in brain aging, meaning they theoretically tested as well as someone two years younger, Dr. Vyas said.

Experts not involved in the research said the study was well designed: it included a large number of participants and used reliable cognitive tests. But the findings “are relatively modest,” said Hussein Yassine, associate professor of neurology at the University of Southern California Keck School of Medicine. While some people may have truly benefited from the multivitamin, he said, most probably haven’t.

The professor added that claiming that a multivitamin could delay cognitive aging by two years “is really an exaggeration.” To reach this conclusion, the researchers compared the performance of the multivitamin group with the average test scores by age. Yassine disagreed with this technique, calling the interpretation “misleading”.

This was also the main concern cited by Pieter Cohen, an internist at Cambridge Health Alliance in Boston who studies supplements. He added that it was unclear whether the subtle improvements measured in people taking multivitamins would be significant.

He said it would be much more convincing if the study found that people who took them were less likely to be diagnosed with Alzheimer’s at a certain age or could live independently for longer.

Manson agreed that more research on multivitamins is needed, especially in groups with more racial, ethnic and socioeconomic diversity. Follow-up studies should look at who benefited from the supplements and why, Yassine added.

It’s possible, for example, that the gains were driven by people who were not previously consuming nutrients important for brain health, such as vitamin B12, vitamin D and zinc.

“Rather than concluding that everyone should take multivitamins, I think we should try to understand who benefits from taking them,” Yassine said.

Multivitamins can be helpful for certain people, such as those with conditions that affect their ability to absorb nutrients, Cohen said, but most healthy people don’t need one. “I will not recommend multivitamins to improve memory based on this data.”

The Cosmos study, funded by the National Institutes of Health and chocolate maker Mars Inc., was originally designed to see whether multivitamins or supplements containing cocoa flavanols would affect the risk of heart disease or cancer. But the trial found little benefit from any supplement.

Other studies have shown that multivitamins did not improve cognition or prevent dementia. For example, in a study of nearly 6,000 male doctors followed for 12 years, those who took a multivitamin did not perform better on cognitive or memory tests than those who took a placebo.

However, research has consistently found that a healthy diet and other lifestyle interventions can benefit the brain. Puja Agarwal, a nutritional epidemiologist at Rush University Medical Center in Chicago, called the new findings “encouraging.” But, she added, “If we can meet our nutritional needs with dietary approaches, that should be the first priority.”