20/10/2025
Vitamin D may slow biological aging, new study finds.
A major clinical trial has found that vitamin D could help slow the body’s aging process – by preserving the protective caps on our DNA.
In a new study published in The American Journal of Clinical Nutrition, researchers followed over 1,000 adults for five years as part of the VITAL trial. Participants who took 2,000 IU of vitamin D daily had significantly less shortening of their telomeres – the protective ends of chromosomes that naturally wear down as we age.
The difference was big enough to translate to nearly three years of reduced biological aging compared to those on a placebo.
Shortened telomeres are linked to age-related diseases like heart disease and certain cancers. By protecting them, vitamin D may support healthier aging at the cellular level – beyond its well-known role in bone health and immune function.
Researchers caution that the results are early. The study only measured telomeres in white blood cells and didn’t track long-term health outcomes. But the findings add to growing evidence that vitamin D may influence how we age – not just how we feel.
["Vitamin D3 and marine ω-3 fatty acids supplementation and leukocyte telomere length: 4-year findings from the VITamin D and OmegA-3 TriaL (VITAL) randomized controlled trial." The American Journal of Clinical Nutrition, July 2025]
Tony Leachon