A large randomized trial suggests that taking a daily multivitamin does not lower blood pressure for most older adults, but it may offer small benefits for people with lower-quality diets or those who start out with normal blood pressure.
The new analysis, published in the American Journal of Hypertension, comes from the COcoa Supplement and Multivitamin Outcomes Study (COSMOS), a long-running trial of nearly 9,000 U.S. adults. Researchers found no differences in rates of newly diagnosed hypertension between the multivitamin and placebo groups overall. But when they looked at certain subgroups, a more nuanced picture emerged.
“Nutrition is one of the cornerstones for controlling blood pressure and hypertension,” said corresponding author Rikuta Hamaya, MD, PhD, MS, of the Division of Preventive Medicine in the Mass General Brigham Department of Medicine. “We found that a daily multivitamin might be useful for reducing the risk of hypertension in people with poorer nutritional intake.”
Participants with lower diet quality scores saw modest reductions in their risk of developing hypertension when taking a multivitamin. A separate group of participants with normal baseline blood pressure also experienced small but measurable decreases over two years.
“Our findings suggest that a daily multivitamin may not be a one-size-fits-all solution for controlling blood pressure but could be beneficial for important subsets of older adults,” said senior author Howard Sesso, ScD, MPH.
The analysis included adults without hypertension at the start of the study who took either Centrum Silver or a placebo for a median of 3.4 years. The research team also examined blood pressure changes in clinic and home measurements. Across the full population, outcomes were the same between the multivitamin and placebo groups.
The authors note that more research is needed, especially in younger adults and groups with varying nutritional status. Their work highlights a recurring theme in nutrition science: supplements may offer small benefits in certain situations, but they do not replace a balanced eating pattern.
This study is part of the long-running COSMOS trial. It was supported by Mars Edge and Haleon, which provided study pills and packaging, and by federal research funding from the National Institutes of Health.