Ask the doctor: Are vitamin D supplements a good idea?

Q. I've heard that low vitamin D levels have been linked to heart disease, so I'm wondering if I should
be taking a vitamin D supplement, just in case. What's your advice?

A. I suggest that you make sure you're getting the Recommended Dietary Allowance for vitamin D, which is 600 international units (IU) for adults up to age 70 and 800 IU for those older than 70. It's true that low vitamin D levels have been linked to heart disease in some studies. However, low vitamin D might just be a consequence of a poor diet and lack of exercise, which can contribute to obesity, heart disease, and a host of other health problems. And to date, there is no evidence that taking additional vitamin D helps prevent or treat any of those conditions, though large studies are ongoing and should provide a definitive answer in the next few years.

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