Daily Multivitamin Shows Modest Functional Health Benefits in Older Adults: COSMOS Trial Secondary Analysis
Key Insights
A secondary analysis of the COSMOS trial found that adults aged 60 and older taking a daily multivitamin for 3 years reported significantly better functional health scores compared to placebo.
The largest improvements were in symptom burden—including fatigue, shortness of breath, and swelling—rather than physical ability alone, as measured by the Kansas City Cardiomyopathy Questionnaire.
Cocoa extract supplementation did not significantly improve functional health overall, but a signal of benefit was observed in participants with congestive heart failure (search).
A new secondary analysis of the large-scale COSMOS trial suggests that daily multivitamin-mineral supplementation may modestly improve cardiovascular-related functional health in older adults over a 3-year period. The findings, presented at NUTRITION 2026, the annual meeting of the American Society for Nutrition (search), indicate that adults aged 60 years and older who took a daily multivitamin reported better functional health than those who received a placebo—including reductions in symptom burden and improvements in overall physical functioning.
The study analyzed data from more than 16,000 participants enrolled in the COcoa Supplement Multivitamins Outcomes Study (COSMOS), a large, randomized, double-blind, placebo-controlled clinical trial designed to test whether taking either a commercially available daily multivitamin (Centrum Silver (search)) or a daily cocoa flavanol supplement could reduce the risk of cancer, cardiovascular disease, and other age-related conditions in older adults. Participants were randomly assigned to receive either a daily multivitamin, a cocoa extract supplement, both supplements, or matching placebos.
Measurable Improvements in Symptom Burden
After 3 years, researchers found that those taking a daily multivitamin had significantly better functional health scores than those taking a placebo, based on the Kansas City Cardiomyopathy Questionnaire—a validated tool that measures symptoms, physical limitations, and quality of life related to cardiovascular health. Notably, the largest differences were seen in symptom burden and the clinical summary score, which combines measures of symptoms and physical function.
The benefits were primarily driven by reductions in symptom burden, including fatigue, shortness of breath, and swelling, rather than improvements in physical ability alone. These functional health benefits may support daily activities and everyday independence, such as walking, climbing stairs, dressing, bathing, and completing household chores.
"Multivitamin-mineral supplementation may help preserve functional health in older adults with heart failure, particularly by reducing symptom burden such as fatigue, edema, and shortness of breath," said Jennifer Wong, MD, a board-certified cardiologist and medical director of Non-Invasive Cardiology at MemorialCare Heart and Vascular Institute (search) at Orange Coast Medical Center in Fountain Valley, CA. Wong was not involved in the study.
Cocoa Extract and Heart Failure: A Signal Worth Pursuing
Unlike multivitamins, cocoa extract did not significantly improve functional health scores across the overall study population. However, researchers observed a significant benefit among those living with congestive heart failure (search), suggesting this finding warrants further investigation.
"The finding that cocoa extract may help preserve symptom burden in people with heart failure is an encouraging signal," Wong added. "However, larger, well-designed clinical trials are needed to determine whether cocoa extract provides meaningful and reproducible clinical benefits before it can be recommended as part of routine care."
Context: Functional Health and Healthy Aging
Functional health refers to a person's ability to perform routine daily activities independently. Health experts consider preserving this ability as an important component of healthy aging, as declines in physical function can reduce quality of life and increase the need for support. The researchers state that the study focused on outcomes that matter directly to older adults, noting that maintaining functional health may help older adults continue everyday activities.
The observed benefits suggest that multivitamins could reflect improvements in several aspects of health, including cognitive function, blood circulation, and physical stamina. However, the current study was not designed to determine the biological mechanisms responsible for the effects.
Limitations and Clinical Perspective
The findings have not yet been published in a peer-reviewed journal and, as such, are preliminary. The study authors emphasize that multivitamins should complement, rather than replace, established healthy lifestyle habits, such as healthy eating, regular physical activity, and social connection.
"While these findings are encouraging, additional research is needed to determine whether these benefits translate into improved long-term clinical outcomes," Wong commented.
"At this time, multivitamins should be viewed as a complement—not a substitute—for healthy lifestyle habits," Wong emphasized. "A heart-healthy diet, regular physical activity, adequate sleep, and appropriate medical care remain the cornerstones of healthy aging."
For anyone considering a new supplement, it is advisable to discuss it with a healthcare professional, particularly those with underlying medical conditions or who take prescription medications, as some vitamins and minerals can interact with certain treatments. Wong further noted: "For some individuals, particularly those with nutritional deficiencies or heart failure, multivitamin supplementation may provide additional benefit, but it should be considered an adjunct to these proven strategies rather than a replacement."