Many people take daily Vitamin D supplements for their benefits to the immune system, bones, and muscles. New research finds they may help slow aging, too.

The American Journal of Clinical Nutrition recently published the results of the VITAL Telomere trial. The goal of the research was to see whether five years of daily Vitamin D3 or omega 3 fatty acid supplementation benefitted telomeres. Telomeres are protein structures of repeating DNA sequences that stop the ends of chromosomes from becoming frayed or attaching to the other chromosomes. A breakdown of telomeres is part of the aging process and is linked with several aging-related diseases. Though there wasn’t a significant benefit from a daily gram of omega 3 fatty acids, the trial showed that 2000 IU per day of Vitamin D3 helped maintain telomere length.

Dr. Haidong Zhu, the study’s first author and molecular geneticist at the Medical College of Georgia, Augusta University, says, “Our findings suggest that targeted vitamin D supplementation may be a promising strategy to counter a biological aging process, although further research is warranted.”

For this study, which involved more than 1,000 participants, telomere length measurements were taken before the study began and then taken again at the two-year and four-year marks. The team found that, when compared to placebo, Vitamin D3 significantly reduced telomere length loss over four years, with this group having longer telomere length than the placebo group. At the four-year mark, 2000 IU of D3 each day reduced telomere attrition by 140 bp, which researchers say reflects nearly three years of prevented aging.

The broader VITAL study (VITamin D and OmegA-3 TriaL), which has involved studying both nutrients’ health impacts on more than 25,000 older adults, has found other benefits for Vitamin D, as well.

Dr. JoAnn Manson, principal investigator of VITAL and chief of the Division of Preventive Medicine at Brigham and Women’s Hospital, explains, “VITAL is the first large-scale and long-term randomized trial to show that vitamin D supplements protect telomeres and preserve telomere length. 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.”

You can read more about the VITAL trial here.