Adults aged 60 and older who took a daily multivitamin for three years reported better functional health than those on a placebo, according to a secondary analysis of the COSMOS trial presented at NUTRITION 2026 on July 27.
The randomized, placebo-controlled study followed more than 16,000 US adults and looked at how well they managed the physical business of everyday life.
The improvements were modest but consistent. Participants on the multivitamin scored higher on symptom burden and on a clinical summary score that averages symptoms and physical ability.
Both scores come from the Kansas City Cardiomyopathy Questionnaire, a self-report tool that captures how heart-related symptoms affect day-to-day function.
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The findings come from a conference abstract and have not yet been peer-reviewed, so treat them as preliminary. Abstracts pass a review committee before selection, but the numbers can still shift before a study reaches a journal.
What "functional health" really means
Functional health is the plain-language version of a clinical outcome. It covers whether someone can move around comfortably, manage tasks like dressing, cooking and household chores, and keep going without being slowed by fatigue or shortness of breath.
In the COSMOS analysis, that translated into small but measurable gains in how participants rated their own physical function over three years.
Bayu B. Bekele, PhD, a postdoctoral fellow at the Georgia Prevention Institute of the Medical College of Georgia at Augusta University, framed the point in human terms. "Multivitamin use supporting heart health and overall physical function may help maintain the ability to perform everyday activities such as dressing, bathing, walking, climbing stairs, jogging or hurrying, and completing household chores," Bekele said.
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Largest gains in those with narrowed arteries
The strongest signal showed up in a small subgroup of 122 participants with carotid stenosis, a narrowing of the arteries in the neck that can reduce blood flow to the brain and raise the risk of stroke.
In that group, multivitamin supplementation produced clinically meaningful improvements in cardiovascular functional health scores.
Because the carotid subgroup is small, the researchers themselves are calling for more targeted trials to confirm the pattern. And even in the wider study the effect was gentle. Bekele emphasized that the multivitamin group was not suddenly able to do activities the placebo group could not, and that the overall benefit was modest.
Diet and exercise still come first
COSMOS is one of the largest randomized nutrition trials ever run in older adults, which gives its signals weight even when they are small. But a multivitamin is a supplement, not a replacement, and it will not undo a poor diet or a sedentary week.
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Anyone thinking of adding a daily pill, especially alongside prescription medications, should talk with their doctor first. The study was funded by the National Institutes of Health.
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