However, up to 50% of the world's population may not get enough sun, and 40% of U.S. residents are deficient in vitamin D.
This is partly because people spend more time indoors, wear sunblock outside, and eat a Western diet low in good sources of this vitamin.
The recommended daily value (DV) is 800 IU (20 mcg) of vitamin D per day from foods.
If you don't get enough sunlight, your intake should likely be closer to 1,000 IU (25 mcg) per day.
Here are 7 healthy foods that are high in vitamin D.
Salmon is a popular fatty fish and great source of vitamin D.
According to the United States Department of Agriculture (USDA) Food Composition Database, one 3.5-ounce (100-gram) serving of farmed Atlantic salmon contains 526 IU of vitamin D, or 66% of the DV.
Whether the salmon is wild or farmed can make a big difference.
On average, wild-caught salmon packs 988 IU of vitamin D per 3.5-ounce (100-gram) serving, or 124% of the DV. Some studies have found even higher levels in wild salmon — up to 1,300 IU per serving.
However, farmed salmon contains only 25% of that amount. Still, one serving of farmed salmon provides about 250 IU of vitamin D, or 32% of the DV.
Wild salmon contains about 988 IU of vitamin D per serving, while farmed salmon contains 250 IU, on average. That's 124% and 32% of the DV, respectively.
2. Herring and Sardines
Herring is a fish eaten around the world. It can be served raw, canned, smoked, or pickled.
This small fish is also one of the best sources of vitamin D.
Fresh Atlantic herring provides 216 IU per 3.5-ounce (100-gram) serving, which is 27% of the DV.
If fresh fish isn't your thing, pickled herring is also a good source of vitamin D, providing 112 IU per 3.5-ounce (100-gram) serving, or 14% of the DV.
However, pickled herring also contains a high amount of sodium, which some people consume too much of.
Canned sardines are a good source of vitamin D as well — one can (3.8 ounces) contains 177 IU, or 22% of the DV.
Other types of fatty fish are also good vitamin D sources. Halibut and mackerel provide 384 IU and 360 IU per half a fillet, respectively.
Herring contains 216 IU of vitamin D per 3.5-ounce (100-gram) serving. Pickled herring, sardines, and other fatty fish, such as halibut and mackerel, are also good sources.
3. Cod Liver Oil
Cod liver oil is a popular supplement. If you don't like fish, taking cod liver oil can be key to obtaining certain nutrients that are unavailable in other sources.
It's an excellent source of vitamin D — at about 448 IU per teaspoon (4.9 ml), it clocks in at a massive 56% of the DV. It has been used for many years to prevent and treat deficiency in children.
Cod liver oil is likewise a fantastic source of vitamin A, with 150% of the DV in just one teaspoon (4.9 ml). However, vitamin A can be toxic in high amounts.
Therefore, be cautious with cod liver oil, making sure to not take too much.
In addition, cod liver oil is high in omega-3 fatty acids, which many people are deficient in.
Cod liver oil contains 448 IU of vitamin D per teaspoon (4.9 ml), or 56% of the DV. It is also high in other nutrients, such as vitamin A and omega-3 fatty acids.
4. Canned Tuna
Many people enjoy canned tuna because of its flavor and easy storage methods.
It's also usually cheaper than buying fresh fish.
Canned light tuna packs up to 268 IU of vitamin D in a 3.5-ounce (100-gram) serving, which is 34% of the DV.
It's also a good source of niacin and vitamin K.
Unfortunately, canned tuna contains methylmercury, a toxin found in many types of fish. If it builds up in your body, it can cause serious health problems.
However, some types of fish pose less risk than others. For instance, light tuna is typically a better choice than white tuna — it's considered safe to eat up to 6 ounces (170 grams) per week.
Canned tuna contains 268 IU of vitamin D per serving. Choose light tuna and eat 6 ounces (170 grams) or less per week to prevent methylmercury buildup.
5. Egg Yolks
People who don't eat fish should know that seafood is not the only source of vitamin D. Whole eggs are another good source, as well as a wonderfully nutritious food.
While most of the protein in an egg is found in the white, the fat, vitamins, and minerals are found mostly in the yolk.
One typical egg yolk contains 37 IU of vitamin D, or 5% of the DV.
Vitamin D levels in egg yolk depend on sun exposure and the vitamin D content of chicken feed. When given the same feed, pasture-raised chickens that roam outside in the sunlight produce eggs with levels 3–4 times higher.
Additionally, eggs from chickens given vitamin-D-enriched feed may have up to 6,000 IU of vitamin D per yolk. That's a whopping 7 times the DV.
Choosing eggs either from chickens raised outside or marketed as high in vitamin D can be a great way to meet your daily requirements.
Eggs from commercially raised hens contain only about 37 IU of vitamin D per yolk. However, eggs from hens raised outside or fed vitamin-D-enriched feed contain much higher levels.
Excluding fortified foods, mushrooms are the only good plant source of vitamin D.
Like humans, mushrooms can synthesize this vitamin when exposed to UV light.
However, mushrooms produce vitamin D2, whereas animals produce vitamin D3.
Though vitamin D2 helps raise blood levels of vitamin D, it may not be as effective as vitamin D3.
Nonetheless, wild mushrooms are excellent sources of vitamin D2. In fact, some varieties pack up to 2,300 IU per 3.5-ounce (100-gram) serving — nearly three times the DV.
On the other hand, commercially grown mushrooms are often grown in the dark and contain very little D2.
However, certain brands are treated with ultraviolet (UV light). These mushrooms can provide 130–450 IU of vitamin D2 per 3.5 ounces (100 grams).
Mushrooms can synthesize vitamin D2 when exposed to UV light. Only wild mushrooms or mushrooms treated with UV light are good sources of vitamin D.
7. Fortified Foods
Natural sources of vitamin D are limited, especially if you're vegetarian or don't like fish.
Fortunately, some food products that don't naturally contain vitamin D are fortified with this nutrient.
Cow's milk, the most commonly consumed type of milk, is naturally a good source of many nutrients, including calcium, phosphorous, and riboflavin.
In several countries, cow's milk is fortified with vitamin D. It usually contains about 115–130 IU per cup (237 ml), or about 15–22% of the DV.
Because vitamin D is found almost exclusively in animal products, vegetarians and vegans are at a particularly high risk of not getting enough.
For this reason, plant-based milk substitutes like soy milk are often fortified with this nutrient and other vitamins and minerals usually found in cow's milk.
One cup (237 ml) typically contains 107–117 IU of vitamin D, or 13–15% of the DV.
Around 75% of people worldwide are lactose intolerant, and another 2–3% have a milk allergy.
For this reason, some countries fortify orange juice with vitamin D and other nutrients, such as calcium.
One cup (237 ml) of fortified orange juice with breakfast can start your day off with up to 100 IU of vitamin D, or 12% of the DV.
Cereal and Oatmeal
Certain cereals and instant oatmeal are also fortified with vitamin D.
Half a cup (78 grams) of these foods can provide 54–136 IU, or up to 17% of the DV.
Though fortified cereals and oatmeal provide less vitamin D than many natural sources, they can still be a good way to boost your intake.
Foods such as cow's milk, soy milk, orange juice, cereals, and oatmeal are sometimes fortified with vitamin D. These contain 54–136 IU per serving.
Vitamin D and Calcium
Vitamin D is necessary for the absorption of calcium, which plays a key role in maintaining bone strength and skeletal integrity.
Getting enough of both vitamin D and calcium is crucial to maintaining bone health and protecting against disorders like osteoporosis, a condition that is characterized by weak, brittle bones.
Children and adults aged 1–70 need approximately 600 IU of vitamin D per day, and it can come from a combination of food sources and sunlight. Meanwhile, adults over 70 should aim for at least 800 IU (20 mcg) of vitamin D per day.
The daily value (DV), a rating system used on the labels of packaged food, is 800 IU per day.
Calcium needs also vary by age. Children aged 1–8 require about 2,500 mg of calcium daily, and those ages 9–18 need approximately 3,000 mg daily.
Adults ages 19–50 generally require about 2,500 mg daily, which decreases to 2,000 mg daily for those over age 50.
Your body needs vitamin D to absorb calcium. This makes getting enough of both vitamin D and calcium crucial to maintaining bone health and preventing osteoporosis.
The Bottom Line
Spending time in the sun is a good way to get your daily dose of vitamin D. However, sufficient sun exposure is difficult for many people to achieve.
Getting enough from your diet alone may be difficult, but not impossible.
The foods listed in this article are some of the top sources of vitamin D available.
Eating plenty of these vitamin-D-rich foods is a great way to make sure you get enough of this important nutrient.