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Over the past decade, vitamin D (technically a hormone) has become one of the most-researched nutrients: Not only is it critical for bone health, cell growth, immune function and other processes, it may also play a role in preventing inflammation and protecting against several forms of cancer. There’s some controversy around how much you should get: While the recommended daily value (DV) for vitamin D was recently updated to 600 IU per day for adults, some studies suggest a higher intake (as much as 4,000 IU per day) is needed to maintain optimal blood levels. Your body produces vitamin D when UV rays from the sun hit your skin, but during the winter and in northern climates, you may not get enough. Because it’s naturally present in very few foods, mostly animal products, vegetarians are at a high risk of deficiency. Here’s how to meet your needs in the gray days of winter:
Salmon is a rich source of vitamin D, but the amounts vary depending on how the fish are raised. Wild-caught varieties are higher: Some contain as much as 988 IU of vitamin D per serving, compared with farmed salmon, which has only about 25% as much. Tuna, herring, mackerel, catfish and halibut are other good sources of vitamin D.
- Mix canned salmon with Greek yogurt, minced dill and capers.
- Top salmon fillets with Kalamata olives, chopped tomatoes and rosemary and roast until tender.
- Combine cooked salmon with cumin, salsa, green onions and avocado cubes and serve as tacos.
One large, commercially raised egg has about 40 IU of vitamin D, but pasture-raised versions can have up to four times as much. Eggs from chickens that were fed vitamin D– enriched feed may have as much as 500 IU per egg. The vitamin D is concentrated in the yolk, so egg white omelets won’t do it; eat the whole thing.
- Combine eggs, chopped mushrooms, spinach and grated cheese, and bake in muffin tins for mini frittatas.
- Mash hard-boiled egg yolks with avocado and spread on sandwiches.
Mushrooms are the only plant source of naturally occurring vitamin D; they contain a type of sterol, called ergosterol, that converts to D in the presence of sunlight. The primary form produced by mushrooms is D2, which some studies suggest is equally as effective as D3. Amounts vary depending on the type of mushroom; some commercially grown varieties are raised in the dark and contain little vitamin D, but if they’re exposed to UV light, they can contain high amounts: one cup of UV-exposed portobellos, for example, provides more than you need in a day. To make sure you’re getting D, look for mushrooms labeled “UV treated” or “high in vitamin D.”
- Brush portobellos with olive oil and grill until tender.
- Sauté brown mushrooms with leeks and tarragon.
- Toss shiitakes with tamari and garlic and roast until tender.
These small, oily fish in the herring family are also excellent sources of vitamin D, with 200 to 300 IU per serving. Like salmon, they’re also loaded with omega-3 fats and other nutrients. The big plus: canned sardines are super-convenient, and if you buy the bone-in varieties, they’re an excellent source of calcium, with about 350 milligrams per serving.
- Sauté canned sardines with roasted red peppers and arugula and toss with cooked pasta.
- Top pizza with tomato sauce, basil, fresh mozzarella and sardines.
They’re high in vitamin D — a six-oyster serving has around 270 IU of vitamin D — and low in carbohydrates and calories (around 50 calories per serving). Oysters are also loaded with zinc, important for immune function: One serving can have up to 59 milligrams, or about 500% of the DV.
- Simmer oysters with stock, milk, onions and garlic for a simple stew.
- Mix chopped smoked oysters with cream cheese and spread on crackers.
- Top oysters in the shell with lemon and garlic and broil.
While vitamin D doesn’t naturally occur in milk, cheese, yogurt or other dairy products, most varieties have added D. In the 1930s, the United States began fortifying milk with vitamin D to enhance calcium absorption and prevent rickets, a childhood skeletal disease. Dairy from grass-fed or pastured animals is also higher in omega-3 fats and other nutrients.
- Warm full-fat Greek yogurt with minced garlic, parsley and shredded Parmesan cheese for a healthier Alfredo sauce.
- Simmer milk, honey, vanilla and unflavored gelatin, pour into ramekins and let cool until firm.
- Purée milk, frozen cherries and cocoa powder, sweeten to taste and freeze in an ice-cream maker.
Because animal products are the only sources of vitamin D3, vegans, vegetarians or people with dairy sensitivities may be at risk for vitamin D deficiency, so most soy, almond, oat and other plant-based milk substitutes are fortified. Most varieties contain between 15 and 25% of the DV for vitamin D per cup, about the same as cow’s milk. Plus, most are also fortified with calcium for bone health. Fortified orange juice is another good option for vegans, vegetarians or those with dairy sensitivities.
- Blend fortified orange juice, vanilla soy milk and ice cubes until smooth.
- Whisk soy milk with probiotic powder in a bowl, cover with a towel and let stand for 24 hours for dairy-free yogurt.
- Simmer soy milk with cinnamon, cardamom, ginger and vanilla, then whisk in matcha green tea powder.