- Telomeres, the protective caps at the ends of chromosomes, are an important component of healthy aging.
- One study found that vitamin D supplementation helps to minimize the shortening of telomeres, which happens as people get older, and thus may protect against diseases tied to age and biological aging.
- This data adds to the potential protective components of vitamin D, which experts should consider alongside potential risks and additional research.
A study published in The American Journal of Clinical Nutrition examined how omega-3 fatty acid and vitamin D supplementation affected telomere shortening, a natural process that happens with age.
As the authors of this study explained, telomeresTrusted Sourcehelp protect the ends of chromosomes. Telomere shortening might increaseTrusted Source the risk of death and certain diseases.
David Cutler, MD, a board certified family medicine physician at Providence Saint John’s Health Center in Santa Monica, CA, who was not involved in the study, told Medical News Today that “When telomeres become too short, cells enter senescence (a non-dividing state) or apoptosis (programmed cell death). Either condition of cell inactivity or death is thought to contribute to aging and age-related diseases.”
The researchers found that vitamin D supplementation helped minimize telomere shortening in white blood cells, which could help slow down biological aging.
Vitamin D supplementation impacts telomere length
For this study, researchers used data from the VITAL trial. This trial included a representative sample of adults in the United States who received vitamin D3 supplements, omega-3 fatty acid supplements, or both for around five years. It was a double-blind, placebo-controlled study, so some participants received the supplements while others received the placebo. All female participants were at least fifty-five years old, and all male participants were at least fifty.
This data specifically examined a cohort that visited the Harvard Clinical and Translational Science Centre. At baseline and follow-up visits, participants participated in in-person assessments and provided fasting blood samples.
Researchers examined telomere length in leukocytesTrusted Source, which are the body’s white blood cells, among participants who received supplements and those who received the placebo.
Researchers were able to analyze over 2,500 samples from over 1,000 participants. They examined telomere length at baseline and at two- and four-year follow-up, though some data was missing.
They conducted a statistical analysis using models to adjust for various covariates. They also did an exploratory subgroup analysis to see how different factors, such as high blood pressure and diabetes, impacted results.
Vitamin D vs. omega-3 fatty acids
Aside from a higher body mass index in the omega-3 fatty acid supplement group, the placebo and intervention groups had similar baseline characteristics. Missing data was also similar between the two groups.
Vitamin D appeared to have a positive impact on telomere length. Among participants who received vitamin D, there was only minimal shortening of telomere length at two and four years. In contrast, there was substantial telomere shortening in the placebo group at both time points.
Omega-3 fatty acids supplementation appeared to have no significant impact on telomere length.
The subgroup analysis further suggested that the effects of vitamin D on telomere length were significant for participants not taking medication for cholesterol, but not for participants who were taking cholesterol medication. Vitamin D also minimized telomere shortening at a statistically significant level for non-white participants.
There was no significant interaction with body mass index, but researchers did observe that participants who were not obese had significantly minimized telomere shortening. Also, taking omega-3 fatty acid supplements did not appear to impact the role of vitamin D on telomere length.