Supplementing with vitamin D may support your longevity, according to one study.Researchers say that the vitamin slows the shortening of telomeres, the protective caps on the ends of chromosomes that are a key marker of biological age. Experts explain the role of vitamin D in helping you age in a healthy way.

There are so many things you can do to promote healthy aging. Exercising more, eating the right foods, working on your balance, and more may help you maintain mobility and stave off illness for years. Now, research published in The American Journal of Clinical Nutrition suggests a supplement to add to that list: They claim that vitamin D slows aging, per their study. Here’s what the study found, plus the ways that vitamin D may support your longevity.

Meet the Experts: Joseph Mercola, D.O., board-certified family physician and author of Your Guide to Cellular Health; and Amy Davis, R.D., L.D.N., Live Conscious nutrition consultant.

The trial followed more than 1,000 healthy American women over 55 years old and men over 50 for a period of four years. At the end of the study, the researchers found that, compared to a placebo, taking 2,000 international units (IU) of vitamin D3 daily helped slow down the shortening of telomeres. Telomeres are “protective caps on your chromosomes that naturally wear down with age,” explained Joseph Mercola, D.O., board-certified family physician and author of Your Guide to Cellular Health. Telomeres protect DNA during cell division, a process that the body uses to repair and grow. Every time that happens, they get a bit shorter, which makes them a marker of biological age. “When telomeres get too short, your cells can’t divide properly and start to malfunction or die,” Dr. Mercola added. “When they shrink too fast, your risk for things like heart disease, cancer, and premature aging symptoms goes up.”

At the start of the study, participants had varied vitamin D levels, and those who took vitamin D3 had more telomere protection than those who didn’t after four years. “That’s a measurable slowdown in cellular aging,” said Dr. Mercola. Another group in the study took omega-3 supplements and did not experience the same results.

While the study is promising, and there are others like it, there were a few limitations, including the participant pool lacking broad demographic and health diversity, potentially limiting the strength of the findings, explained Amy Davis, R.D., L.D.N., Live Conscious nutrition consultant. Still, both of our experts do think that, in the way of studies, this one was a pretty solid randomized clinical trial. “While more studies would help clarify the full picture, this adds real credibility to vitamin D3’s role in slowing age-related decline,” Dr. Mercola concluded.

How exactly does vitamin D have this effect on chromosomes? More research is needed to determine how it slows telomere shortening, but research suggests it likely has to do with its anti-inflammatory effects, immunity protection, and its role in cell function, particularly within the mitochondria, explained Dr. Mercola. “Your mitochondria are the energy factories of your cells, and keeping them healthy helps preserve your metabolic power, your resilience, and even your brain function,” he said. “Vitamin D also supports the production of glutathione, your body’s master antioxidant. That means less oxidative stress, fewer damaged proteins and membranes, and slower wear and tear on your cells.” According to the Cleveland Clinic, oxidative stress may play a role in everything from cancer to rheumatoid arthritis.

Other ways to promote healthy aging

Of course, as is the case with any supplementation, you should talk to your doctor before going all-in on vitamin D supplements and make sure you’re practicing other healthy habits such as eating a Mediterranean-style diet, exercising regularly, getting good sleep, and maintaining an active social life.

Your body gets vitamin D through sun exposure, which you naturally absorb safely in small increments, said Dr. Mercola. (Still, don’t skip the sunscreen!) “Your body is built to regulate how much vitamin D it makes from sunlight,” he added. “If you supplement, test your levels first.” Your doctor can draw blood and determine if you have a deficiency and if supplements are needed.

Dietary supplements are products intended to supplement the diet. They are not medicines and are not intended to treat, diagnose, mitigate, prevent, or cure diseases. Be cautious about taking dietary supplements if you are pregnant or nursing. Also, be careful about giving supplements to a child, unless recommended by their healthcare provider.

Related Stories