Many people take multivitamins every day in the hope of staying healthy, but scientists have long debated whether these supplements truly make a difference.
A new study led by researchers from Mass General Brigham suggests that taking a daily multivitamin may slightly slow the biological aging process in older adults.
The research found that people who took a multivitamin for two years showed signs of slower aging at the cellular level compared with those who did not take the supplement.
The findings were published in the scientific journal Nature Medicine. According to the researchers, the results suggest that a simple and widely available supplement might help support healthier aging, although more studies are needed to fully understand the long-term effects.
When scientists talk about aging, they often distinguish between chronological age and biological age. Chronological age is simply the number of years a person has lived.
Biological age, however, reflects how quickly the body is aging at the cellular and molecular level. Two people who are the same age in years may have different biological ages depending on their health, lifestyle, and genetic factors.
In recent years, scientists have developed tools called epigenetic clocks to estimate biological age. These clocks measure small chemical changes in DNA known as DNA methylation.
These changes do not alter the DNA sequence itself but influence how genes are turned on or off. Over time, patterns of DNA methylation shift in predictable ways as people age, allowing scientists to estimate how quickly the body is aging.
For this study, researchers used data from a large clinical trial known as COSMOS, which stands for the COcoa Supplement and Multivitamin Outcomes Study. This long-running study investigates whether certain dietary supplements may help reduce the risk of major diseases and improve health outcomes in older adults.
The team analyzed blood samples from 958 participants who were randomly selected from the larger COSMOS trial. The average age of these participants was about 70 years old.
Because the trial was randomized, participants were assigned to different groups to receive specific treatments. Some people took a daily multivitamin along with cocoa extract, others took a multivitamin with a placebo, some took cocoa extract alone, and another group received placebos for both.
By analyzing DNA methylation patterns in blood samples collected at the beginning of the study and again after one and two years, the researchers were able to estimate biological aging using five different epigenetic clocks. These clocks are widely used by scientists to measure aging processes and to predict risks related to health and mortality.
The results showed that participants who took a daily multivitamin experienced slower biological aging across all five epigenetic clocks compared with those who took only placebos. The difference was modest but measurable. On average, the slowing of aging was equivalent to about four months over the two-year study period.
The effect was even stronger in people whose biological age appeared older than their chronological age when the trial began. In other words, individuals whose bodies seemed to be aging faster than expected gained the greatest benefit from the daily multivitamin.
Researchers believe this result may suggest that people with greater nutritional gaps or higher biological stress might respond more strongly to additional vitamins and minerals. However, the exact biological mechanisms behind the effect are still unclear.
The study’s senior author, Dr. Howard Sesso of Mass General Brigham, explained that many people are interested in ways to not only live longer but also remain healthy and active as they age.
Discovering that a daily multivitamin might influence markers of biological aging is an encouraging finding, especially because multivitamins are inexpensive and widely available.
Even so, scientists caution that the results should be interpreted carefully. The slowing of aging observed in the study was relatively small, and biological aging is a complex process influenced by many factors including diet, exercise, genetics, sleep, and overall health.
The researchers also plan to conduct further analyses to determine whether the changes in biological aging markers continue after the trial ends. Another important question is whether the slowing of biological aging helps explain other potential health benefits observed in the COSMOS trial.
Previous analyses from the same study have suggested that daily multivitamin use may improve certain aspects of cognitive function and may reduce the risk of some conditions such as cancer and cataracts. If these benefits are linked to slower biological aging, it could provide important clues about how vitamins support overall health.
However, it is important to remember that taking supplements alone cannot replace healthy lifestyle habits. A balanced diet, regular physical activity, good sleep, and avoiding smoking remain some of the most powerful ways to support long-term health and healthy aging.
Overall, the study provides interesting new evidence that daily multivitamins may influence biological aging at the cellular level. While the effect appears modest, the results suggest that accessible nutritional interventions might play a role in supporting healthy aging.
Future research will be needed to confirm these findings, understand how multivitamins influence aging biology, and determine whether the benefits translate into longer and healthier lives.
If you care about nutrition, please read studies about the power of beetroot juice, and the risks of mixing medications with dietary supplements.
For more health information, please see recent studies about how to boost iron intake: natural solutions for anemia, and results showing vitamin K may lower your heart disease risk by a third.
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