Study finds vitamin D supplements could reduce biological aging by 3 years

A new study led by researchers at Mass General Brigham and the Medical College of Georgia has revealed that vitamin D supplements may do more than just support bone health — they could also help slow down the aging process at a cellular level. The study, published in The American Journal of Clinical Nutrition, found that taking vitamin D supplements may protect against biological aging by slowing the shortening of telomeres, the tiny caps on DNA that naturally erode as people grow older.

The study, conducted as part of a nationwide four-year trial, tracked over 1,000 U.S. adults (men over 50 and women over 55) who were randomly assigned to take either a placebo or a daily dose of vitamin D3 (2,000 IU) and omega-3 fatty acids (1 gram). Telomere length in white blood cells was measured at the start of the study, at the two-year mark, and after four years. The researchers found that participants taking vitamin D3 had significantly less telomere shortening compared to those in the placebo group. In contrast, omega-3 supplements had no significant effect on telomere length throughout the follow-up period.

Telomeres are made of repeating sequences of DNA that act like protective tips at the ends of chromosomes, preventing chromosome ends from degrading or fusing with other chromosomes. Over time, these DNA caps shorten, which is a natural part of aging and is linked to a higher risk of age-related diseases. Scientists view telomere length as a marker of biological age, which may better reflect a person’s health status than their actual age in years.

The study’s co-author, Dr. JoAnn Manson, highlighted the significance of the findings, stating that this was the first large-scale, long-term randomized trial to show that vitamin D supplements protect telomeres. Previous phases of the trial had already shown that vitamin D supplementation could reduce inflammation and lower the risk of certain chronic age-related conditions, such as advanced cancers and autoimmune diseases.

While the new findings on telomere length don’t conclusively prove that vitamin D slows aging overall, researchers believe it points to a potentially powerful way to protect the body at the cellular level. Dr. Haidong Zhu, the study’s first author, emphasized that targeted vitamin D supplementation may be a promising strategy to counter the biological aging process, but further research is needed to fully understand the impact of vitamin D on aging in different populations and over longer timeframes.

Before starting a new supplement regimen, experts recommend consulting with a healthcare provider to discuss proper dosage and potential risks. The findings of this study suggest that vitamin D may play a role in preserving telomeres, which are linked to the development of certain diseases as they shorten with age. More research is needed to determine the long-term effects of vitamin D supplementation on aging, but the potential benefits are promising.