Vitamin D may slow biological aging

A new study reports that vitamin D supplementation may help slow some of the mechanisms of biological aging.
The research, published in The American Journal of Clinical Nutrition, suggests that vitamin D may help maintain the stability of telomeres, the protective caps at the end of chromosomes that tend to shorten as people get older.
That shortening is a natural part of aging, but it has been linked to certain age-related diseases. Among those diseases are cancer of the bladder, lungs, kidneys, and gastrointestinal systems.
“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 Haidong Zhu, MD, PhD, the first author of the study and a molecular geneticist at the Medical College of Georgia, Augusta University, in a statement.
Experts agree the new research is interesting, but they note it has its limits.
“Telomere length was protected with vitamin D supplementation, but it’s not clear how that translates to real life biological aging,” Marilyn Tan, MD, a clinical associate professor of medicine at Stanford University in California, told Healthline. Tan wasn’t involved in the study.
“The present study involved only a relatively small number of people, looked only at telomeres in white blood cells, and did not look extensively at the health impact of these telomere changes,” added David Cutler, MD, a family medicine physician at Providence Saint John’s Health Center in Santa Monica, California. “So, the clinical implications one can derive from this study are quite limited.” Cutler was likewise not involved in the study.
The findings were based on the results of the VITAL randomized controlled clinical trial, which was overseen by Brigham and Women’s Hospital in Boston.
The researchers sought to find out whether a daily vitamin D dosage of 2,000 individual units (IUs) and 1 gram per day of omega-3 fatty acids could minimize telomere shortening and slow biological aging.
A total of 1,054 participants were included in the sub-study, which included females 55 and older and males 50 and older. The researchers followed the participants for five years, measuring telomere length in white blood cells at baseline, year two, and year four.
The researchers reported that omega-3 fatty acids had no significant effect on telomere length.
However, they said vitamin D3 supplements significantly reduced telomere shortening and prevented the equivalent of nearly three years of aging in people who took vitamin D in comparison to people who were given a placebo.
Experts say such a slowdown in the aging process has important benefits.
“Slowing biological aging may improve life expectancy and quality of life, and it could reduce the risk of various disease states,” Tan said.
The health benefits of vitamin D have been touted over recent years.
An October 2024 study reported that vitamin D supplementation can help lower blood pressure as well as cholesterol levels.
Previous research has also indicated that a sufficient amount of vitamin D may help improve heart health.
A July 2020 study suggested that people with prediabetes may want to take vitamin D supplements to lower their risk of developing type 2 diabetes.
Vitamin D is also known to improve bone health and help prevent osteoporosis.
In addition, low vitamin D levels have been linked to chronic inflammation as well as psoriasis.
High vitamin D levels, on the other hand, can reportedly cause elevated blood calcium levels as well as gastrointestinal issues and kidney complications.
It’s estimated that 35% of people Trusted Source in the United States have a deficiency of vitamin D.
The current recommendation Trusted Source for daily vitamin D consumption is 400 to 800 international units for most healthy people. (Healthline)