Fatty fish and cod liver oil top the list of foods naturally highest in vitamin D. A single tablespoon of cod liver oil delivers 1,360 IU, while a 3-ounce serving of cooked swordfish provides 566 IU. For context, most adults need 600 IU per day, so one serving of either food covers your daily requirement and then some.
Fatty Fish: The Richest Natural Sources
No food category comes close to fatty fish for vitamin D content. Here’s how the top options compare per 3-ounce serving:
- Swordfish (cooked): 566 IU
- Salmon (pink, canned): 493 IU
- Spanish mackerel (raw): 248 IU
A single serving of swordfish or salmon nearly covers an entire day’s worth of vitamin D for adults under 70. Even mackerel, the lowest on this list, still provides about 40% of the daily recommendation. Wild-caught fish generally contain more vitamin D than farmed varieties because wild fish accumulate it through their natural diet of plankton and smaller fish. Canned salmon is a convenient, affordable option that holds up well nutritionally.
Cod Liver Oil
Cod liver oil is the single most concentrated food source of vitamin D available. One tablespoon contains 1,360 IU, more than double what most adults need daily. It also packs 13,600 IU of vitamin A, which is worth noting because vitamin A can cause problems in excess. If you’re already taking a multivitamin or eating liver regularly, the extra vitamin A from cod liver oil could push you past safe levels. For people who just want the vitamin D, fish oil supplements (which come from fish body fat rather than the liver) offer vitamin D without the heavy vitamin A load.
Fortified Foods
Outside of seafood, very few foods contain meaningful amounts of vitamin D naturally. That’s why fortification plays such a large role in how most people actually get this nutrient. In the United States, milk, plant milks, and orange juice are the most common fortified options:
- Soy milk (unsweetened): 119 IU per cup
- Low-fat cow’s milk (1%): 117 IU per cup
- Skim milk: 115 IU per cup
- Fortified almond milk: 107 IU per cup
- Fortified rice milk: 101 IU per cup
- Fortified orange juice: 100 IU per cup
These numbers cluster tightly around 100 to 120 IU per cup, meaning you’d need about five to six cups of fortified milk or juice daily to meet the 600 IU recommendation from these foods alone. Realistically, fortified foods work best as a supplement to fish, eggs, or mushrooms rather than as your sole source. One thing to watch: not all plant milks are fortified. Check the label, because unfortified versions contain virtually zero vitamin D.
Eggs, Mushrooms, and Other Sources
Egg yolks contain vitamin D, though in modest amounts compared to fish. A single large egg yolk provides roughly 40 IU, so you’d need a lot of eggs to make a dent. Still, eggs contribute meaningfully if you eat them regularly alongside other sources.
UV-exposed mushrooms are the only significant plant-based source of naturally occurring vitamin D. When mushrooms are grown under ultraviolet light (or even placed in sunlight after harvest), they produce vitamin D2. Maitake mushrooms and UV-treated portabellas can provide several hundred IU per serving. The catch is that mushrooms produce D2 rather than D3, and D2 is less effective at raising your blood levels. Vitamin D3, found in animal foods, is converted to its active form more efficiently in your body. So while mushrooms count, you may need larger amounts to get the same benefit as you’d get from fish.
D3 vs. D2: Why the Source Matters
Vitamin D comes in two forms. D3 (from animal sources and sunlight) raises blood levels of vitamin D more efficiently than D2 (from plants and fungi). Taking D2 alongside D3 can actually reduce D3’s effectiveness, so people who rely on a mix of sources should be aware that not all vitamin D is equal on a unit-for-unit basis. If you’re choosing between a D2 supplement (often labeled as ergocalciferol) and a D3 supplement (cholecalciferol), D3 is the stronger option for maintaining healthy blood levels.
Cooking Doesn’t Destroy Vitamin D
Unlike some vitamins that break down with heat, vitamin D is remarkably stable during cooking. Research on pork found that household cooking methods actually increased the measurable concentration of vitamin D3 by about 49%, largely because water and fat cook out of the meat, leaving the vitamin D more concentrated in what remains. Retention rates exceeded 100% across nearly every cooking method tested, with sous-vide cooking producing the highest retention at 135%. So whether you bake, fry, or simmer your salmon, you’re keeping the vitamin D intact.
How Much You Actually Need
The recommended daily intake varies by age. Adults between 19 and 70 need 600 IU (15 mcg) per day, while adults over 70 need 800 IU (20 mcg). Infants need 400 IU. These recommendations assume minimal sun exposure, so if you spend regular time outdoors with skin exposed, your dietary needs may be lower.
Vitamin D is fat-soluble, meaning your body absorbs it best when you eat it alongside some dietary fat. This happens naturally with the richest sources (fatty fish, egg yolks, fortified whole milk) since they already contain fat. If you’re taking a supplement or drinking fortified skim milk, pairing it with a meal that includes some fat will improve absorption.
Building a realistic daily intake might look like a serving of salmon (493 IU) plus a glass of fortified milk (117 IU), which easily exceeds 600 IU. Or, if fish isn’t part of your routine, two glasses of fortified plant milk (about 220 IU), two eggs (80 IU), and some UV-exposed mushrooms can get you close, though a D3 supplement may help fill the gap.