Vitamin D Is Key to a Healthy Immune System, and These 7 Foods Have It in Spades

Adults require about 600 to 800 IU of vitamin D each day, according to the Institute of Medicine. One serving of farmed salmon contains nearly a third of your daily vitamin D needs. Not only does salmon supply your body with vitamin D, but it's also loaded with immune-supporting omega-3 fatty acids. Specifically, choosing Chilean farmed salmon gives you more omega-3s compared to other types of fish, with no mercury or antibiotics.

All mushrooms contain some vitamin D, but some varieties boast even more due to UV light or sunlight exposure. Mushroom farmers literally expose mushrooms to UV light to increase their vitamin D content!

A simple and delicious way to add vitamin D to your diet is blending finely chopped mushrooms with ground meat in dishes such as burgers, tacos, or bolognese. Swapping just 25 percent of the meat for mushrooms will reduce your calorie and fat intake, while adding nutrients like vitamin D, potassium, B vitamins, and antioxidants.

You may want to skip the egg-white-only omelette and go for the whole egg if you're trying to get in your daily dose of vitamin D. The yolk is a nutrition powerhouse, containing this important nutrient, along with other key vitamins and minerals for immune support, like selenium. Eggs are one of the only foods that naturally has vitamin D. Whether you eat them hard-boiled, scrambled, or fried, don't skip that yolk!

If you're keeping fortified orange juice on hand, know that one 250 millilitre glass gives your body a whopping 15 percent of the daily value of vitamin D, along with 100 percent of your daily vitamin C. What's more, 100 percent orange juice contains a natural plant chemical, or flavonoid, that may offer health benefits to humans. In fact, data suggests that among those who consumed flavonoids, there was a 33 percent decrease in upper respiratory tract infections, compared with those who did not consume flavonoids.

While milk doesn't naturally contain vitamin D, it is almost always fortified with this nutrient — a practice that dates back to the 1900s, when the nutrient was added to combat an increase in rickets cases. Enjoying a glass of milk is a simple way to give your body a boost of vitamin D, regardless of whether you're choosing skim, whole, or anything in between.

Hamburger lovers, rejoice! Beef is a natural source of vitamin D, as well as other immune-supporting nutrients like zinc. In fact, lower levels of zinc were associated with greater inflammation and poorer outcomes in hospitalised COVID-19 patients, compared with more healthful levels, according to a recent study. Enjoying lean beef in moderation can be a part of a healthy diet, especially in the colder months when sun exposure is limited, and thus our ability to make our own vitamin D is hindered.

Eating oysters supplies your body with a boost of vitamin D, along with healthy fats and vitamin B12. Whether you enjoy them sautéed, grilled, or even as a pizza topping, there is no wrong way to indulge in these delicacies.