Should You Take a Multivitamin for Your Brain?

Popping a multivitamin every morning at breakfast may be a habit that your mother instilled in you as a child. Next to your cereal bowl, you found a chewable, teddy-bear-shaped tablet meant to make you grow big and strong or stay focused at school. Not just for kids, about 4 in 10 people 60 and older take a multivitamin, according to the Centers for Disease Control and Prevention. Broaden to all vitamin and dietary supplements​, and that number jumps to almost ​8​ in 10 adults 50 and older taking them, according to a 2021 AARP survey. 

Until recently, the expert advice on supplements has been: If you don’t have a documented vitamin deficiency, don’t waste your money.

But when it comes to brain health, the tide may be turning for one type of supplement ​—​​ multivitamins.

Evidence is mounting in favor of a role for multivitamins in brain health, thanks in large part to a randomized controlled clinical trial called COSMOS (COcoa Supplement and Multivitamin Outcomes Study). More than 21,000 adults 60 and older took either cocoa extract supplements, multivitamins or ​a ​​​placebo. In separate studies, researchers examined the supplements’ effects on risk for heart disease, stroke and cancer, as well as cognitive decline. ​Three separate COSMOS studies have supported the benefits of a multivitamin for brain health.

In the COSMOS-Mind study, researchers followed 2,262 whose average age was 73, for three years. Through yearly phone calls, they assessed participants’ thinking skills and found that those taking the daily multivitamin saw much smaller declines in overall cognition, episodic memory and executive function over the years than those in the cocoa and placebo groups. Their brain operated like the brain of someone nearly two years younger at the end of the study period. The benefits were most pronounced in people who had heart disease. These findings were published in Alzheimer’s ​&​​ Dementia in 2022. 

In 2023, the COSMOS-Web study, published in The American Journal of Clinical Nutrition, randomized 3,562 older adults to take a daily multivitamin or placebo. After a year, those in the multivitamin group performed​ better on memory recall tests than their counterparts in the placebo group. By the three-year mark, they had slowed declines in recall by ​more than​ three years compared with the placebo group. 

Most recently, COSMOS-Clinic, published in The American Journal of Clinical Nutrition in 2024, further bolstered the case for multivitamins. This study tracked nearly 500 adults 60 and older for two years and found that those in the multivitamin group significantly slowed down their losses in episodic memory compared with those not taking multivitamins. 

More research is needed to confirm the effect. The evidence is strongest for following a brain- and heart-healthy diet, says Sarah Lenz Lock, senior vice president for policy and brain health at AARP. 

If you want to try a daily multivitamin for brain health, talk to your doctor or a pharmacist about safe dosing and possible interactions with your other medications. Over-the-counter​​ supplements can interfere with both prescription and OTC medications. The supplement could make other drugs ineffective or cause potentially serious side effects. There’s also a risk of getting too much of some nutrients. Take stock of how much of the essential vitamins and minerals you get from your diet — including foods to which vitamins are added, such as cereal, bread and OJ — and make sure you’re not megadosing.