Taking a vitamin D supplement – or getting enough of the compound naturally – can knock three years off your biological aging, according to the results of a large, long-term study. This may not seem like a lot, over a lifetime, but it's a significant amount as you become more and more susceptible to age-related diseases.
Co-led by researchers at Mass General Brigham and the Medical College of Georgia, the The VITamin D and OmegA-3 TriaL (VITAL) study enrolled 25,871 US males aged 50 years and older and females aged 55 years and older to study a range of health biomarkers potentially impacted by both omega-3 and vitamin D supplementation. A subset of 1,054 participants featured in the VITAL Telomere study, where this biological aging marker was the focus.
What they found was that, when assessed at baseline and then again after two and then four years, the subset of participants who had been receiving vitamin D3 (2,000 IU/day) had significantly longer telomeres within their white blood cells than those receiving a placebo. (Omega-3 fatty acid had no effect on this health biomarker.)
So, what has this got to do with anti-aging? Telomeres are the protective "caps" on the ends of chromosomes, essentially shielding the important DNA held within from degrading or fusing with other chromosomes. They naturally shorten with every cell division, and there's a growing body of evidence linking this to limited stem cell function and organ health. As such, short telomeres have been linked to a suite of age-related conditions and diseases.
“VITAL is the first large-scale and long-term randomized trial to show that vitamin D supplements protect telomeres and preserve telomere length,” said co-author JoAnn Manson, MD, principal investigator of VITAL and chief of the Division of Preventive Medicine at Brigham and Women’s Hospital. “This is of particular interest because VITAL had also shown benefits of vitamin D in reducing inflammation and lowering risks of selected chronic diseases of aging, such as advanced cancer and autoimmune disease.”
Until now, studies into telomere length and vitamin D have been small and brief, and produced mixed results. The VITAL Telomere study is the first to show, with robust trial design over a long period, that the compound does indeed appear to offer great benefit in shielding the breakdown of these chromosome caps.
“Our findings suggest that targeted vitamin D supplementation may be a promising strategy to counter a biological aging process, although further research is warranted,” said first author Haidong Zhu, a molecular geneticist at the Medical College of Georgia, Augusta University.
For humans, vitamin D3 and D2 are the most important in this group of fat-soluble compounds, helping with a range of functions including bolstering the immune system and helping the absorption of calcium – which is also very important for bone health in aging. A deficiency has also more recently been linked to age-related dementia and neurological conditions in newborns.
That said, there are as many studies that have found no evidence that it can ward off depression, and more research is needed to support claims that it can ease the severity of viruses like COVID-19 and the measles.
While it's hard to measure what our bodies absorb from natural sources – food, the Sun – this 2,000 IU/day dose is largely considered safe for most people, with the limit set at around twice that amount. However, it's best to talk to your healthcare provider to make sure there are no other risk factors before upping your D dose.
The study was published in the American Journal of Clinical Nutrition.
Source: Mass General Brigham