New research suggests a daily multivitamin may help combat the cellular wear and tear associated with ageing. In a randomised study of 958 older adults, those who took a multivitamin daily for two years experienced slowed biological ageing by about four months. While chronological age tracks time since birth, biological age reflects wear and tear on the body at a cellular level. Factors such as genetics, lifestyle habits, and medical history mean a 50-year-old might have a biological age of 47 or 54.

The COSMOS Trial Results

The findings were published Monday in Nature Medicine—one of the world's highest-impact and most rigorously peer-reviewed medical journals. The data stems from theCocoaa Supplement and Multivitamin Outcomes Study (COSMOS), a massive, multi-year research initiative involving over 21,000 participants and led by investigators from Harvard Medical School and Mass General Brigham. This specific trial focused on healthy older adults—men 60 and older and women 65 and older—with an average chronological age of 70. Participants were randomly assigned to one of four groups: cocoa extract and a multivitamin; a multivitamin; cocoa extract; or a placebo."

Measuring Cellular Decay

Researchers used five "epigenetic clocks" to analyse small changes in DNA. Two "second-generation clocks" that gauge mortality, PCGrimAge and PCPhenoAge, showed ageing slowed by 1.4 and 2.6 months, respectively. One clock, DunedinPACE, is licensed to TruDiagnostic and was co-invented by Daniel Belsky, an associate professor at Columbia University.

“I think of biological ageing as the progressive loss of the integrity and resilience capacity of cells, tissues and organs with the passage of time,” Belsky said. “Happens to all of us. It’s the leading cause of almost all chronic diseases and death.” Cocoa extract was found to have no effect on any of the five measures of biological ageing.

Health Trajectories vs Lifespan

Howard Sesso, the study’s senior author from Harvard Medical School, cautioned that a multivitamin does not simply add four months to a person’s lifespan. “What it means is that your trajectory of health moving forward should stand to benefit,” Sesso said. “It’s hard to know what those four months truly translate to.” Those exhibiting accelerated biological ageing at the outset saw the greatest benefit, with some results doubling the slowing of PCGrimAge to 2.8 months.

Funding and Transparency

The study was funded in part by Haleon (formerly Pfizer Consumer Healthcare) and Mars Inc., which provided the supplements. Sesso and another author received funding from both companies, though neither corporation contributed to the research design.

Scientific Scepticism and Limitations

Some experts remain cautious. Danica Chen, a professor at UC Berkeley, noted that while the biomarkers are "cutting-edge," the field is still looking for "proof of concept." “We do not know yet whether [multivitamins] have an effect in improving tissue function or reducing disease risk,” Chen said. She is also interested in seeing whether results hold long-term, noting that the study period was only two years. Furthermore, most participants were white, leaving it unclear how these findings apply to more diverse populations, particularly across sub-Saharan Africa, where distinct genetic and environmental factors play a role.

The Role of Nutrition and Economics

Healthy ageing remains a multifaceted process. Joanne Slavin, a professor at the University of Minnesota, pointed out that older adults face unique challenges, such as difficulties opening cans or reading labels. Across the continent, these hurdles are sharpened by a "dual burden" of malnutrition. As inflation drives the cost of nutrient-dense staples beyond the reach of many—with over 13 million Ghanaians facing food insecurity by late 2024—the practicality of a balanced diet becomes an economic struggle. Supermarket prices increased by 2.1% recently, and Slavin noted that it is difficult to isolate which ingredient drives the results. “Is it vitamin C? Is it folic acid?” Slavin said. “We don’t know.”

Clinical Recommendations

Experts agree that while the link is modest, it is realistic. “Nobody thinks taking a multivitamin is going to rejuvenate them,” Belsky said. Sesso maintains that supplements should not replace a balanced diet or medical consultation. This is particularly critical in our region, where geriatric specialists are few; many African nations operate with fewer than five trained geriatricians, leaving the health of our elders largely in the hands of family and primary care providers. “The decision to take a multivitamin is still one that should always be taken into consideration with your healthcare provider,” Sesso said. However, for those already taking them, he added, “there’s no reason to stop.”

The Evolving Science of Longevity

While a four-month shift in cellular ageing may seem subtle, it signals a shift in how science approaches the "healthspan" of a rapidlygreyingg African population. For our elders navigating high food costs and the physical hurdles of daily life, these findings offer a pragmatic, low-cost layer of biological resilience. In societies where traditional community-led care remains the bedrock of support for the aged, such accessible interventions could prove vital. As research moves from proof-of-concept toward long-term clinical strategy, the multivitamin may prove to be a modest but essential ally in ensuring that, as we live longer, we also live better.