Recent studies indicate that daily intake of multivitamins and minerals may slow cognitive decline in individuals over 60, and now, evidence suggests these supplements could potentially slow aging on a broader scale.

However, the findings are based on indirect aging measures, making it unclear what this means in terms of health advantages. Currently, medical experts, including Howard Sesso from Harvard University, advise against universally recommending multivitamins for older adults. He notes, “While we haven’t seen significant adverse effects, the benefits are still uncertain.”

Historically, it has been claimed that individual vitamins provide various health benefits, but this approach can sometimes be harmful. For instance, excessive vitamin A can weaken bones and too much vitamin B3 may cause liver damage. Additionally, high levels of vitamin B6 can result in loss of sensation in limbs. The UK Health Service recommends that everyone take vitamin D, usually during winter months.

Multivitamin supplements, like Centrum Silver utilized in this research, typically contain recommended daily intake amounts. According to Sesso, “These doses are not excessive.”

To investigate potential effects, Sesso and his team randomly assigned 1,000 participants with an average age of 70 to either receive the supplement or a placebo. “This was a rigorously designed, randomized, double-blind, placebo-controlled trial,” he explains. Steve Horvath from UCLA, not involved in the study, remarks, “This distinction differentiates us from much of the supplement research, which often relies on observational data riddled with confounding factors.”

Researchers collected blood samples from participants at the study’s outset, one year later, and again two years later. They analyzed the DNA from immune cells, looking for epigenetic markers—chemical tags added to DNA—at specific genomic locations.

Epigenetic markers change predictably with age, enabling researchers to estimate a person’s biological age through blood tests. Various epigenetic clocks have been developed, differing based on which genomic segments are analyzed.

Sesso’s research utilized five epigenetic clocks, all indicating that individuals taking multivitamins exhibited slightly younger biological profiles than those taking a placebo. However, significant results were only evident in two clocks. According to Horvath, “The significant results stemmed from second-generation clocks, which have emerged as the most reliable for evaluating longevity interventions.”

While first-generation clocks are effective for predicting age, many markers they observe are not inherently linked to health, Horvath points out. In contrast, second-generation clocks are built upon markers associated with health risks and mortality. “Nonetheless, the effect size remains modest,” he adds. “This is certainly not a miracle solution for aging.”

“The observed differences were minimal compared to the variation in participants prior to the intervention,” states Daniel Belsky from Columbia University.

The researchers determine that the epigenetic clock lag they discovered equates to approximately four months over two years. However, this may not convey the entire picture. Belsky explains that how age-related improvements correlate with conventional time drastically varies across different clocks.

Sesso acknowledges the ambiguity surrounding the health implications of these epigenetic measures. “Understanding how a four-month reduction in biological aging translates into clinical benefits is still a mystery,” he admits.

Most study participants were of European descent, leaving uncertainty about whether these slight reductions in epigenetic aging apply to non-Europeans or younger demographics. The longevity of these results when using different multivitamins also remains undetermined.

While the study is complete, the potential effects of cocoa extract were also assessed, with some participants taking it in conjunction with their vitamins or as a placebo substitute. Notably, cocoa extract did not yield any significant effects on the epigenetic clocks.