Exploring the Link Between Vitamin D and Healthy Aging

Some scientists distinguish between chronological age—the number of candles on your birthday cake—and biological age, which refers to how much your cells seem to have aged. Your biological age may be different from your chronological age.

If you have a higher biological age, you’re more likely to get age-related diseases such as cancer and heart disease. On the bright side, you can influence your biological age with diet and lifestyle changes. A 2022 study found that taking vitamin D supplements helped slow down biological aging among participants with vitamin D deficiency.

These results are consistent with a 2020 study, which found that participants who got enough vitamin D showed signs of slower biological aging than those who did not. With this in mind, it’s no surprise that a 2023 review in the International Journal of Molecular Sciences hailed vitamin D as a “shield against aging.”

While these studies are promising, they aren’t conclusive. What we know for sure, though, is that vitamin D is crucial for our health—and many of us aren’t getting enough of it.

The National Institutes of Health (NIH) generally recommends that adults get 600 IU of vitamin D per day—unless you’re over the age of 70, in which case you should aim for 800 IU. However, other experts suggest that up to 1,500 to 2,000 IU of daily vitamin D is best for optimal well-being.

Don’t hit the NIH’s recommendation? You’re not alone. More than one-third of American adults aren’t getting the vitamin D they need. People in Canada don’t fare any better, with 32 percent of Canadians missing out on the sunshine vitamin. The good news is that a simple blood test can tell you whether you are one of them.

Being deficient in vitamin D can cause loss of bone density, which may lead to weak bones or even osteoporosis. More common in older adults, osteoporosis causes bones to break easily. Research has also linked low levels of vitamin D to faster cognitive decline.

Your body produces vitamin D when it’s exposed to sunlight. In many situations, 10 to 15 minutes in the sun a few times per week is sufficient. But your exact needs will vary based on your age, environment, skin pigmentation, clothes, and other factors.

For many people, getting enough vitamin D from sunlight is easier said than done—especially in the depths of winter. It can be tough to get the sunlight you need when days are short and you’re bundled up in a heavy coat whenever you leave home. Fortunately, sunlight isn’t the only source of vitamin D. You can get vitamin D through food, including cheese, mushrooms, egg yolks, beef liver, and fatty fish like salmon.

Supplements are the main treatment for vitamin D deficiency. Many older adults, in particular, benefit from supplements because they have difficulty absorbing vitamin D. Other groups that can especially benefit from vitamin D supplements include people with darker skin, those who don’t live in sunny environments, and those with certain medical conditions like obesity or liver disease.

It should come as no surprise that vitamin D might slow down biological aging, because it’s known to counteract some of the problems that come with it. For example, vitamin D may help combat the loss of bone density and muscle strength that often comes with age. Some research suggests it may also reduce your risk of cancer, type 2 diabetes, and cognitive decline.

Getting too much vitamin D can do more harm than good, so it’s important to stay within a safe range. This is typically a maximum of 4,000 IU per day for adults (from all sources combined). Keep in mind, too, that vitamin D supplements can interact with certain medications. Ultimately, if you’re not getting enough of the sunshine vitamin from food and sunlight, supplements are a bright way to get a boost—just make sure to check with your healthcare practitioner to assess your unique needs.