• Mayo Clinic Minute: How much vitamin D do you need?

Studies show that, while most Americans do not get enough vitamin D, a growing portion of people get too much. Finding a happy medium does not have to be tricky.

Watch: The Mayo Clinic Minute

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Even though it's one of the most important nutrients for keeping your muscles strong and your bones from breaking, most Americans do not get enough vitamin D.

"A substantial proportion of the population may well have what we would call either vitamin D insufficiency, where it's kind of borderline low, or frank vitamin D deficiency," Sundeep Khosla, M.D., says.

Khosla is an endocrinologist at Mayo Clinic and says exposure to sunlight is the easiest way to get vitamin D. He says, generally, 30 minutes a day does the trick.

But getting 30 minutes of sunlight a day can be tough for a lot of people, especially during the winter. So, Khosla says people can fill some of the gaps with food and drinks.

Most dairy products these days are fortified with vitamin D, as are some other items like orange juice.

But Khosla says vitamin D-filled food options are limited.

"So for many people, taking a vitamin D supplement is perhaps the best way to ensure adequate vitamin D amounts. And for most people, somewhere between 600 and 800 units of vitamin D ─ which is, in fact, what most multivitamins now contain ─ is sufficient to maintain adequate vitamin D levels," Khosla says.

But recent studies show excessive vitamin D supplements might lead to kidney and heart issues, an increase in fractures and falls, and even certain types of cancer.

"I think the bottom line is you need to get enough vitamin D; 600 to 800 units is probably enough," Khosla says.