Older adults who took a daily multivitamin for three years reported meaningfully better day-to-day functioning than those who took a placebo, according to a new analysis of one of the largest supplement trials ever run.
The finding has not been peer reviewed. It was presented on July 27 as a conference abstract at NUTRITION 2026, the annual meeting of the American Society for Nutrition, and it is a secondary analysis rather than the trial's main question. Both of those facts belong at the top, because supplement findings tend to travel much further than their evidence supports.
What makes it worth reporting anyway is the outcome the researchers chose. Most large supplement trials count heart attacks, cancers, and deaths. This one asked whether people could still do the things that make daily life workable.
What "Functional Health" Meant Here
The researchers analyzed data from more than 16,000 adults aged 60 and older enrolled in the COcoa Supplement and Multivitamin Outcomes Study, known as COSMOS. Participants were randomly assigned to a daily multivitamin, a cocoa extract supplement, both, or neither, with placebos used for the control group and for those taking only one supplement.
Functional health was measured using the Kansas City Cardiomyopathy Questionnaire, a scored instrument that asks people about symptom burden and about how much difficulty they have with ordinary activities. In practice, that means questions touching on fatigue, breathlessness, and whether tasks like carrying groceries or climbing stairs have become harder.
Bayu B. Bekele, PhD, a postdoctoral fellow at the Georgia Prevention Institute of the Medical College of Georgia at Augusta University, presented the work with Yanbin Dong, MD, PhD, who directs the institute. Bekele described the analysis's distinguishing feature as its focus on how people actually feel and function in their daily lives rather than on preventing major disease.
Why a Self-Reported Score Is a Real Limitation
The endpoint is the strength of this analysis and also its weakness, and the two cannot be separated.
Asking people how they are functioning captures something objective tests miss. A person can pass a walking test and still find that everything takes more effort than it used to. But a self-reported score also captures mood, expectation, and how a person feels about the study they are in, and none of those are the same as physical capability.
There is a second wrinkle specific to the instrument. The Kansas City Cardiomyopathy Questionnaire was developed and validated for patients with heart failure, not as a general measure of aging. Applying it to a broad population of older adults is defensible for comparing two randomized groups against each other, but it makes the result harder to translate into a familiar benchmark.
No objective physical performance testing was reported alongside these results. Until measured outcomes such as gait speed or grip strength point in the same direction, the honest description is that people on a multivitamin said they were doing better, not that they demonstrably were.
What the Analysis Found
After three years, participants assigned to the multivitamin reported significantly better functional health scores than those assigned to placebo. The researchers characterized the improvement as modest, and reported that participants described less fatigue and less breathlessness than the placebo group.
Cocoa extract did not produce a significant improvement across the study population as a whole. It was associated with a benefit among participants who had congestive heart failure, which is a subgroup finding in a secondary analysis and should be treated as a lead for future work rather than a result.
This sits alongside earlier COSMOS work. A separate ancillary study published in the American Journal of Clinical Nutrition found that daily multivitamin supplementation improved immediate recall memory at one year among older adults, with the effect sustained across three years, while finding no significant effect on memory retention, executive function, or novel object recognition. The pattern across COSMOS has been small positive signals on some measures and nothing on others.
Who Paid for It
COSMOS is not a straightforwardly independent trial, and readers deserve that context up front rather than in a footnote.
The multivitamin used in COSMOS was Centrum Silver, and the study pills and packaging were donated by Pfizer Consumer Healthcare, now Haleon, which markets that product. Mars Edge, the nutrition arm of Mars Incorporated, provided infrastructure support and donated the cocoa extract pills. The investigators have stated that neither company had a role in trial design, conduct, data collection, analysis, or manuscript preparation. This particular analysis was supported by National Institutes of Health grant HL157665.
A company donating the product being tested is common in nutrition research and does not by itself invalidate a result, particularly in a randomized placebo-controlled design. It is still a fact a reader should have when deciding how much weight to put on a favorable finding about a commercial supplement.
What This Should and Should Not Change
Nothing here supports treating a multivitamin as a substitute for anything. The researchers said as much, emphasizing that supplements are not replacements for a balanced diet or regular physical activity.
For a healthy older adult already eating reasonably well, a daily multivitamin is inexpensive and low risk, and this analysis is a modest point in its favor. For anyone with a diagnosed deficiency, a malabsorption condition, or a restricted diet, the relevant conversation is about targeted testing and treatment, not a general-purpose tablet.
Certain groups should talk with a clinician before starting one. People taking warfarin need to know that vitamin K content matters. People with hemochromatosis or other iron overload conditions should avoid iron-containing formulas. Anyone taking thyroid medication, certain antibiotics, or bisphosphonates should ask about timing, because minerals in a multivitamin can interfere with absorption. Fat-soluble vitamins accumulate, so stacking a multivitamin on top of separate high-dose supplements is where problems tend to start.
Larger doses are not better, and a supplement will not fix an underlying reason that daily tasks are getting harder. New or worsening breathlessness, unexplained fatigue, or a sudden loss of stamina in an older adult warrants a medical evaluation rather than a trip to the vitamin aisle.
Researchers said future work using objective physical tests will be needed to determine how much of the reported improvement reflects measurable change. Until this analysis is published in a peer-reviewed journal with full numbers, the appropriate posture is interest rather than confidence.
Frequently Asked Questions
What did the analysis find? That older adults taking a daily multivitamin for three years reported significantly better functional health scores than those on placebo, with the improvement described as modest.
Has this been peer reviewed? No. It was presented as a conference abstract at NUTRITION 2026. Abstracts are selected by a review committee but are not peer-reviewed publications, and figures can change before journal publication.
How was functional health measured? With the Kansas City Cardiomyopathy Questionnaire, a self-reported score covering symptom burden and difficulty with daily activities. It was developed for heart failure patients.
Does this prove multivitamins improve physical function? No. Participants reported feeling better. No objective physical performance testing was reported alongside this result.
Who funded and supplied the trial? The study pills were donated by Pfizer Consumer Healthcare, now Haleon, which makes Centrum Silver, and by Mars Edge. Investigators say neither company had a role in design or analysis. This analysis had NIH funding.
Should I start taking a multivitamin? That is a decision to make with a clinician, particularly if you take warfarin, thyroid medication, bisphosphonates, or have an iron overload condition.
What about the cocoa extract? It showed no significant benefit across the study population overall. A benefit appeared in participants with congestive heart failure, which is a subgroup signal, not a conclusion.
