Soak up the sun while downing some dairy for a dose of vitamin D. The nutrient is key for healthy bone growth, and proper immune, nerve, and muscle function. But here’s the kicker: Most Americans are vitamin D deficient, which can lead to serious health risks, such as osteoperosis, heart disease, and high blood pressure.Demographic differences and trends of vitamin D insufficiency in the US population, 1988-2004. Ginde AA, Liu MC, Camargo CA. Archives of internal medicine, 2009, Apr.;169(6):1538-3679. Prevalence and correlates of vitamin D deficiency in US adults. Forrest KY, Stuhldreher WL. Nutrition research (New York, N.Y.), 2011, May.;31(1):1879-0739. So what's the best way to avoid these problems and get enough D?

Far From The D-List: The Need-to-Know

Drink Vitamin D Fortified Milk for Health

Vitamin D is a fat-soluble vitamin that the body needs for calcium absorption, cell growth, immune system function, and inflammation reduction. The major function of this important vitamin is to maintain normal levels of calcium and phosphorus in the blood. Without enough vitamin D, bones can’t properly develop, leading to diseases like osteoporosis and rickets.

Vitamin D comes from three sources: sunlight, food, and supplements. The key to getting enough is finding a good mix of all three sources—it’s impossible to efficiently get enough from just one source. So how much is enough? The National Institute of Health recommends that adults between 19 and 50 years of age get 15 mcg (or 600 IUs) of vitamin D per day. That's equal to about one vitamin D-fortified six-ounce yogurt (80 IUs), two large eggs (82 IUs), or one 3-ounce serving of cooked salmon (447 IUs) combined! The problem is that vitamin D isn't naturally present in very many foods, which is why vitamin D-fortified products like cereal, orange juice, and milk are hitting the shelves left and right.

Without enough vitamin D, bones can’t properly develop, leading to diseases like osteoporosis and rickets.

If going au natural, keep in mind these vitamin D-rich foods: egg yolks, fish (specifically salmon, mackerel, bluefish, and canned tuna), and sun-ripened mushrooms. While sunlight is the most efficient way to get the full daily dose of vitamin D, don’t grab a beach towel and slide on those Ray-Bans just yet. One study suggests that oral supplements and dietary sources are the safest ways to increase vitamin D levels. That's because it's hard to measure the amount of sun exposure, and UV radiation can have some dangerous health effects.Estimated equivalency of vitamin D production from natural sun exposure versus oral vitamin D supplementation across seasons at two US latitudes. Terushkin V, Bender A, Psaty EL. Journal of the American Academy of Dermatology, 2010, Apr.;62(6):1097-6787. Intakes of calcium and vitamin D and breast cancer risk in women. Lin J, Manson JE, Lee IM. Archives of internal medicine, 2007, Jun.;167(10):0003-9926. Systematic review: Vitamin D and calcium supplementation in prevention of cardiovascular events. Wang L, Manson JE, Song Y. Annals of internal medicine, 2010, Mar.;152(5):1539-3704.

But be careful about popping those vitamin D pills! Getting too much vitamin D (typically from supplements) can cause a decrease in appetite, nausea, and even vomiting. (And no, that's not why the Gallon Challenge causes vomiting too.)

Originally published July 2012. Updated February 2016.

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