Do You Need to Take Vitamin D Supplements in Wintertime? Here’s What the Experts Say

vitamin d winter
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I get asked this often, especially this time of year, when days get shorter and people spend less time outside. Vitamin D is an important nutrient for your bone health. Furthermore, there’s research to suggest vitamin D supplements could reduce prostate, colon, and skin cancer risk. If you live in places like Alaska or the Northeast, where sun exposure—a source of vitamin D—is appreciably lower, you may benefit from supplements. But too much of it isn’t good, either. Taken in excess, vitamin D becomes a risk factor for some diseases it should protect against—including cancer. Too much can also increase your absorption of calcium, leading to problems such as kidney stones and damage to your heart and blood vessels. The National Academy of Medicine recommends an upper limit of 4,000 international units a day to be safe.

When a patient asks about supplements, I take the opportunity to talk to them about the real changes they can make that will keep them healthy. In looking at the scientific literature, the health benefits of supplements are not clear. I’m not saying they’re bad—it’s just not that simple. Eat a diet that helps you maintain a healthy weight and lower inflammation, such as the Mediterranean diet, or eating vegetarian. And exercise, too. Many of us want a magic pill, but it doesn’t exist.

Have a question for Dr. Choi? Email him at AskDrChoi@MensJournal.com.

Benjamin Choi, M.D., is a urologist in New York City and a clinical assistant professor of urology at Weill Cornell Medicine.

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