While you probably know that the body produces vitamin D when exposed to sunlight, there are also other ways to get the crucial nutrient.
However, there are only a handful of foods that contain the nutrient naturally, part of the reason why only about 20 percent of our vitamin D comes from our diet, according to WebMD.
Most of the vitamin D that we do get from the foods we eat comes from fortified foods, according to the Office of Dietary Supplements, like orange juice, milk and cereal.
Some people opt to take vitamin D supplements to reach the 600 International Units (IUs) recommended for most adults. (As many as 4,000 IUs a day may still be safe, Scientific American reported, and could provide even greater health benefits.)
But, especially as the days get shorter, it becomes harder to spend time soaking up the sun, and you shouldn't spend too much time sunscreen-free anyway. To get the most vitamin D from your diet possible, try adding these natural sources to your meals today.
There are a number of seafood options with a hearty dose of vitamin D. Salmon is high on the list; three ounces of canned sockeye clocks in at <a href="http://nutritiondata.self.com/facts/finfish-and-shellfish-products/4113/2">nearly 650 IUs</a>, more than you need in one day. And three ounces of <em>fresh</em> sockeye has <a href="http://ndb.nal.usda.gov/ndb/foods/show/4529">almost 450 IUs</a>.
Three ounces of light tuna canned in water <a href="http://ndb.nal.usda.gov/ndb/foods/show/4563">packs 154 IUs</a>, nearly a third of your daily recommended intake. Tuna packed in oil <a href="http://ndb.nal.usda.gov/ndb/foods/show/4562">contains even more vitamin D</a>, but be aware that oil means more fat.
Another canned option is sardines. Two of the little fish pack <a href="http://ndb.nal.usda.gov/ndb/foods/show/4531">46 IUs</a>, about 13 percent of your daily recommended value.
One large egg yolk contains <a href="http://ndb.nal.usda.gov/ndb/foods/show/113">37 IUs of vitamin D</a>. Eggs are also a great source of protein, and while, yes, they <a href="http://www.sparkpeople.com/resource/nutrition_articles.asp?id=126">do contain dietary cholesterol</a>, they haven't been linked with an increased risk of heart problems -- so go ahead and make 'em sunny side up.
A slice of Swiss contains about <a href="http://ndb.nal.usda.gov/ndb/foods/show/40">6 IUs</a> and is less processed (and <a href="http://www.fitnessmagazine.com/recipes/healthy-eating/nutrition/get-more-vitamin-d-healthy-foods-to-add-to-your-diet/?page=5">contains less sodium</a>) than a cheese like American, Fitness magazine reported. A cup of ricotta cheese has <a href="http://ndb.nal.usda.gov/ndb/foods/show/36">25 IUs</a>, but we'd suggest a smaller amount, since it's also high in fat.
Three ounces of liver contains <a href="http://ods.od.nih.gov/factsheets/VitaminD-HealthProfessional/">42 IUs of vitamin D</a>, and while it might not be the first thing you reach for, liver also happens to be a <a href="http://www.huffingtonpost.com/2012/03/05/iron-in-foods-the-best-di_n_1316332.html">good source of iron</a>.
Certain fungi, <a href="http://www.huffingtonpost.com/paul-stamets/mushrooms-vitamin-d_b_1635941.html">when exposed to more sunlight</a>, or to indoor ultraviolet light, can contain beneficial levels of vitamin D. Since most mushrooms are grown in the dark, check for <a href="http://www.eatingwell.com/nutrition_health/nutrition_news_information/vitamin_d_fortified_mushrooms">sun-grown brands</a> at a store near you.
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