Do Multivitamins Help You Live Longer? Maybe Not, Says a New Study

While we want most of our nutrients to come from food, many people—about 1 in 3 adults in the United States—take a multivitamin to help fill nutritional gaps in their diet. And while it has been shown that taking a multivitamin may help delay cognitive decline and improve brain function in older adults, many take multis hoping they will help them be healthier and live longer. But will they?

Researchers from the National Institutes of Health wanted to know, too. Here’s what they found from their study published on June 26, 2024, in JAMA Network Open.

How Was This Study Conducted & What Did It Show?

Researchers took data from three large U.S. cohort studies: the National Institutes of Health-AARP Diet and Health Study (NIH-AARP); the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial; and the Agricultural Health Study (AHS). A total of 390,124 participants were included, about 55% of them male and 45% of them female, with an average age of about 62. 

Participants were in good health with no history of major chronic diseases at the beginning of the study and were followed for up to 27 years. During that time, 164,762 participants died—49,836 to cancer, 35,060 to heart disease and 9,275 to cerebrovascular diseases. 

In addition to questions about multivitamin use, age and sex, participants also responded to questions about race and ethnicity, education level, smoking status, BMI, marital status, physical activity level, alcohol intake, coffee intake, diet, other individual supplement use and family history of cancer. 

After several statistical analyses were run, including before and after adjusting for demographic variables (confounders), the researchers concluded that daily multivitamin use is not associated with longevity. In other words, taking a multivitamin won’t help you live longer. 

Interestingly, during the first 12 years of follow-up, researchers found that compared to those who didn’t take multivitamins, those who took multivitamins actually had a 4% increased risk of dying. That risk disappeared, though, during the last 15 years of follow-up.

How Does This Apply to Real Life?

While this study did not find that you can add years to your life by taking a multivitamin, as previously mentioned, multivitamins can have some positive effects on brain health. People who have difficulty eating enough or who have difficulty absorbing nutrients may also benefit from taking a multivitamin. Some signs that you might need one include poor nail health, impaired night vision, cracked corners around your mouth and bruising easily. 

And if you just want to make sure you’re covered, it’s OK to take one, too. Just remember that multivitamins are intended to supplement a balanced diet, not replace it. And take only the recommended dose. It’s easy to overdo it on vitamin and mineral supplements. Over time, as they build up in your body, it could cause toxicity—especially the fat-soluble vitamins A, D, E and K, as well as calcium and iron.

If you do decide to take a multivitamin, choose one that has been third-party tested to ensure that what the label says is what you’re actually getting. Some stamps of approval to look for include Consumer Lab, NSF International and US Pharmacopeia (USP). 

And although a multivitamin may not add years to your life, certain lifestyle habits might—like frequently moving your body, eating a plant-forward diet, avoiding smoking and fostering positive relationships.  

The Bottom Line

While regularly taking a multivitamin might not help you live longer, it probably doesn’t hurt to take one to ensure you’re getting the nutrients you need for your brain and overall health. We recommend having a conversation with your health care practitioner or a registered dietitian first to make sure taking one is right for you. If you decide to take one, choose one that has been third-party tested. And above all, engage in healthy habits and keep a smile on your face.