Fatty fish is the single best food source of vitamin D, with a 3-ounce serving of canned pink salmon delivering nearly 500 IU. That’s close to the full daily recommendation of 600 IU for most adults. But fish isn’t your only option. Fortified foods, eggs, mushrooms, and a few other sources can all contribute meaningful amounts to your intake.
How Much You Need Each Day
Most adults between 19 and 70 need 600 IU (15 mcg) of vitamin D daily. Adults over 70 need 800 IU (20 mcg). Infants need 400 IU. These numbers, set by the National Academies of Sciences, Engineering, and Medicine, represent a baseline for bone health and normal calcium metabolism. Many people fall short because very few foods contain vitamin D naturally, and sun exposure varies wildly depending on where you live, the season, and your skin tone.
Fatty Fish: The Top Tier
No food category comes close to fatty fish for naturally occurring vitamin D. A 3-ounce serving of canned pink salmon provides about 493 IU, covering roughly 82% of the daily target for most adults. Spanish mackerel delivers around 248 IU per 3-ounce raw serving. Trout, swordfish, and tuna are also reliable sources, generally falling in the 150 to 600 IU range per serving depending on the species and preparation.
Cod liver oil is in a league of its own. A single tablespoon contains about 1,360 IU of vitamin D, more than double the daily recommendation. It also packs 13,600 IU of vitamin A, which is worth knowing because vitamin A can cause problems at high doses over time. If you already eat liver or take a multivitamin, adding cod liver oil on top could push your vitamin A intake too high.
Eggs: Yolks Matter Most
Vitamin D in eggs is concentrated entirely in the yolk. A single conventional egg yolk contains a modest amount, typically around 40 IU, so eggs alone won’t get you to your daily target. But they add up as part of a varied diet, especially if you eat eggs regularly.
How the hens are raised makes a real difference. Research comparing production systems found that free-range and organic eggs contained about 42% more vitamin D3 than eggs from indoor-housed hens. The reason is straightforward: hens with access to sunlight synthesize more vitamin D in their skin, and that vitamin D ends up in the yolk. If your grocery store labels eggs as “free-range” or “pasture-raised,” the vitamin D content is likely meaningfully higher than standard indoor eggs.
Mushrooms: The Only Plant That Makes Vitamin D
Mushrooms are unique in the plant world. Like human skin, they produce vitamin D when exposed to ultraviolet light. The catch is that commercially grown mushrooms are typically raised in the dark, so they contain almost none. Standard untreated portabella mushrooms have roughly 10 IU per 100 grams, which is negligible.
UV-treated mushrooms tell a very different story. When exposed to UV light for just 15 to 20 seconds, portabellas jump to around 446 IU per 100 grams. USDA testing found that levels in treated mushrooms ranged from 140 to 752 IU per 100 grams depending on the producer. Many grocery stores now sell mushrooms labeled “UV-treated” or “high in vitamin D” on the packaging. These are one of the few meaningful whole-food sources for people who don’t eat fish.
One important distinction: mushrooms produce vitamin D2, while animal sources contain vitamin D3. Your body handles D3 more efficiently. Research shows D3 raises blood levels of vitamin D about twice as effectively as D2, partly because the liver enzyme responsible for processing vitamin D has a stronger affinity for D3, and partly because D2 breaks down faster in the body. UV-treated mushrooms still contribute to your vitamin D status, but gram for gram, the vitamin D from fish or eggs does more.
Fortified Foods
Most of the vitamin D in the average American diet comes from fortified foods rather than naturally rich sources. The FDA allows manufacturers to add up to 84 IU of vitamin D3 per 100 grams of cow’s milk, which works out to roughly 120 IU per cup. Plant-based milk alternatives like soy, oat, and almond milk can be fortified with up to 84 IU of vitamin D2 per 100 grams. Orange juice is another common vehicle for fortification, with similar levels.
Fortified cereals typically contain 40 to 80 IU per serving. Some yogurts and margarines are also fortified, though amounts vary by brand. Checking the nutrition label is the only reliable way to know, since fortification is voluntary. A glass of fortified milk plus a bowl of fortified cereal at breakfast can provide around 200 IU before you’ve eaten anything else.
How Cooking Affects Vitamin D
Vitamin D is relatively stable compared to some other vitamins, but cooking method and time both matter. Boiling eggs retains 86 to 88% of their vitamin D content. Frying preserves a similar amount, around 82 to 84%. But baking foods in an oven for 40 minutes at standard cooking temperatures drops retention down to 39 to 45% for eggs and margarine. Bread holds up better during baking, with wheat bread retaining about 85% of its vitamin D3.
The takeaway is practical: quick, high-heat methods like frying and boiling preserve more vitamin D than long oven baking. If you’re counting on eggs or fortified margarine for part of your daily intake, a scrambled egg on the stovetop gives you roughly twice the vitamin D of an egg baked into a casserole for 40 minutes.
Vegan Sources Beyond Mushrooms
If you eat no animal products at all, your options for naturally occurring vitamin D are essentially limited to UV-treated mushrooms. Everything else in a vegan diet relies on fortification: plant milks, fortified cereals, fortified orange juice, and fortified plant-based yogurts.
For supplements, most vitamin D3 is derived from lanolin in sheep’s wool, which isn’t vegan. However, vitamin D3 extracted from lichen (a symbiotic organism of algae and fungi) is now widely available. These lichen-derived supplements provide the more effective D3 form rather than D2, typically in doses of 1,000 to 2,500 IU per capsule. For vegans who get limited sun exposure, a lichen-based D3 supplement combined with fortified foods is the most reliable strategy for maintaining adequate levels.
Putting It Together
Reaching 600 IU daily from food alone is realistic but requires some intention. Two servings of fatty fish per week can cover a large portion of your needs. On non-fish days, a combination of fortified milk or plant milk, eggs, and UV-treated mushrooms can fill the gap. A rough example: one cup of fortified milk (120 IU) plus two eggs (80 IU) plus a serving of UV-treated mushrooms (around 200 IU) gets you to 400 IU from food, with sun exposure or a small supplement covering the rest.
People who eat little or no fish, live at northern latitudes, have darker skin, or spend most of their time indoors are at higher risk of falling short. For these groups, fortified foods and a supplement are often necessary regardless of diet quality, simply because vitamin D is rare in the food supply and sun exposure is unreliable for much of the year.