Multivitamins or Saw palmetto supplement capsules

(© Michelle Lee Photography -

🔑 Key Findings:

  • Taking multivitamins daily may slow brain aging by 2 years
  • Supplements with more than 20 essential micronutrients prevented memory loss

BOSTON — Taking a daily multivitamin may help slow brain aging significantly, potentially preventing or delaying Alzheimer’s disease, a new study suggests. The finding adds to a long back-and-forth debate over whether multivitamins are actually beneficial. Many recent studies suggest the popular supplements don’t provide much value to individuals, even if they follow a poor diet. 

This latest study bucks the trend. It emerged from research conducted by the team at Mass General Brigham, who analyzed data from the expansive COcoa Supplement and Multivitamin Outcomes Study (COSMOS). The work involved a detailed analysis of cognitive functions among 21,442 American adults aged 60 and above.

The research included a meta-analysis of over 5,000 participants across three separate COSMOS cognitive substudies, providing robust evidence of the benefits of multivitamin supplements. This rigorous investigation was unique in its approach, employing in-person, comprehensive neuropsychological assessments to capture subtle changes across multiple cognitive domains.

A specific focus of the study was on episodic memory, the ability to recall personal experiences and events, a key aspect of cognitive health that often deteriorates with age. The results were striking. Over a period of two years, participants who took daily multivitamins showed a significantly more favorable change in episodic memory compared to those who received a placebo.

Moreover, study authors estimate that the multivitamin use potentially slowed cognitive aging by two years. However, there was no significant impact on executive function or attention observed.

“Cognitive decline is among the top health concerns for most older adults, and a daily supplement of multivitamins has the potential as an appealing and accessible approach to slow cognitive aging,” says first author Chirag Vyas, MBBS, MPH, instructor in investigation at the Department of Psychiatry at Massachusetts General Hospital (MGH), in a media release.

Historically, the effectiveness of multivitamins in preventing cognitive decline has been far from clear. Prior studies, such as the Physicians’ Health Study II, which relied on telephone-based cognitive assessments, found no significant benefits of multivitamins on cognition. However, the COSMOS study’s in-person assessments provided a more nuanced and detailed understanding of cognitive function, revealing subtle improvements that previous studies may have missed.

“The meta-analysis of three separate cognition studies provides strong and consistent evidence that taking a daily multivitamin, containing more than 20 essential micronutrients, helps prevent memory loss and slow down cognitive aging,” adds Vyas, a founding member of the Mass General Brigham healthcare system.

Woman holding vitamin or multivitamin pill
Study authors estimate that the multivitamin use potentially slowed cognitive aging by two years. (© insta_photos –

These findings are especially relevant given that nearly one in four Americans will be over 65 by 2060, a demographic particularly vulnerable to cognitive decline and diseases like Alzheimer’s. The study suggests that a simple, accessible intervention like a daily multivitamin-mineral supplement could have substantial public health implications, potentially delaying the onset of cognitive decline and associated diseases.

It’s important to note that while the results are promising, they represent an average effect, and individual responses to multivitamin supplementation can vary. Moreover, supplements should not replace a balanced diet and healthy lifestyle but could be considered a complementary strategy for cognitive health in older adults.

“These findings will garner attention among many older adults who are, understandably, very interested in ways to preserve brain health, as they provide evidence for the role of a daily multivitamin in supporting better cognitive aging,” adds Olivia Okereke, MD SM, senior author of the report and director of Geriatric Psychiatry at MGH.

The study also highlights that this is the third COSMOS experiment to praise daily multivitamins in this way – adding even more weight to the findings.

“The finding that a daily multivitamin improved memory and slowed cognitive aging in three separate placebo-controlled studies in COSMOS is exciting and further supports the promise of multivitamins as a safe, accessible and affordable approach to protecting cognitive health in older adults,” concludes JoAnn Manson, co-author of the report and Chief of the Division of Preventive Medicine at Brigham and Women’s Hospital.

The findings are published in the American Journal of Clinical Nutrition.

South West News Service writer Imogen Howse contributed to this report.

About StudyFinds Staff

StudyFinds sets out to find new research that speaks to mass audiences — without all the scientific jargon. The stories we publish are digestible, summarized versions of research that are intended to inform the reader as well as stir civil, educated debate. StudyFinds Staff articles are AI assisted, but always thoroughly reviewed and edited by a Study Finds staff member. Read our AI Policy for more information.

Our Editorial Process

StudyFinds publishes digestible, agenda-free, transparent research summaries that are intended to inform the reader as well as stir civil, educated debate. We do not agree nor disagree with any of the studies we post, rather, we encourage our readers to debate the veracity of the findings themselves. All articles published on StudyFinds are vetted by our editors prior to publication and include links back to the source or corresponding journal article, if possible.

Our Editorial Team

Steve Fink


Chris Melore


Sophia Naughton

Associate Editor


  1. Christina says:

    My cats love dreamies chicken flavour

  2. Tom Cool says:

    There is more and more info on this all the time. A good sized dose of coconut oil helps diabetics retain their memory because their bodies use oil instead of carbs to run the bran.