How to Get Enough Vitamin D
Many people have trouble meeting their daily needs
Few nutrients seem to get as much attention as vitamin D does. Taking a supplement has been touted as an effective way to slow overall aging and protect against heart disease and cancer, although science doesn’t always back up such claims. And while some people might take megadoses of the vitamin, many others might not be getting enough. Here are answers to five questions that will help you keep your vitamin D levels on track.
What Does Vitamin D Do in the Body?
Its main job is helping your body absorb calcium, a mineral that strengthens bones as well as tooth enamel. Vitamin D also assists with controlling blood sugar, which is important for preventing type 2 diabetes.
How Much Vitamin D Do You Need Per Day?
The recommended daily intake for vitamin D is 600 IU for adults up to age 70 and 800 IU if you’re older. People usually don’t get enough from their diet, says Anastassios G. Pittas, MD, a professor of medicine at the Tufts University School of Medicine in Boston. Your body makes vitamin D when the sun’s UV rays hit your skin, but habits like wearing sunscreen (important for preventing skin cancer) can cut the amount that’s produced.
What Foods Have Vitamin D?
A limited number of foods naturally contain vitamin D, but some others, like milk and cereal, are often fortified with it. Good sources include the following:
Sockeye salmon: 570 IU per 3 ounces, cooked
2% milk (fortified): 120 IU per cup
Almond, soy, and oat milks (fortified): 100 to 144 IU per cup
Cereal (fortified): 80 IU per serving
Sardines: 46 IU in two
Egg: 44 IU
Canned light tuna: 40 IU per 3 ounces
Cheddar cheese: 17 IU per 1.5 ounces
Should You Take a Vitamin D Supplement?
Everyone should consider a daily 1,000- to 2,000 IU supplement as insurance, Manson says. That’s especially key for older adults. “As you age, you make less vitamin D from the sun and absorb less from food,” Pittas says. He recommends a 4,000 IU supplement for those with prediabetes. But taking more could lead to muscle spasms, fatigue, kidney stones, and even coma. So talk with your doctor first.
How Do You Choose the Right Supplement?
The Food and Drug Administration doesn’t review supplements for safety and efficacy, so Manson advises looking for brands verified by NSF International or U.S. Pharmacopeia (USP). You may also wonder if you should take vitamin D2 or D3. Research shows that D3 raises blood levels of vitamin D higher and for longer periods. D3 is typically made from a fatty substance in sheep’s wool, while D2 comes from yeast and mushrooms (so it works for vegans). Whichever form you use, take it with food that contains healthy fats, such as avocados, nuts, and olive oil. Vitamin D needs fat to be properly absorbed.
Editor’s Note: This article also appeared in the January 2026 issue of Consumer Reports On Health.
