Foods High in Vitamin D: Top Sources and Normal Thyroid Function

The foods highest in vitamin D are fatty fish such as trout and salmon, cod liver oil, mushrooms exposed to UV light, and fortified foods like milk, plant milks and breakfast cereals. Eggs, beef liver and canned tuna add smaller amounts [1]. Vitamin D is not a thyroid nutrient in the way iodine is, but it is studied for its links to normal thyroid and immune function, and that research is summarized below.

Evidence grade: Strong. Food amounts, daily needs and the upper limit are established NIH reference values; the thyroid research reported below is mostly observational with a smaller number of trials.

Top Foods High in Vitamin D

The table lists foods from the NIH Office of Dietary Supplements food table, from the richest source down. The percent Daily Value (DV) is based on 20 mcg (800 IU), the amount food labels use [1].

Fatty fish and cod liver oil

The flesh of fatty fish, including trout, salmon, tuna and mackerel, and fish liver oils are among the best natural sources [1]. A single 3-ounce portion of trout or sockeye salmon comes close to, or exceeds, the 15 mcg most adults need.

Mushrooms

Mushrooms contain variable amounts of vitamin D2. Some mushrooms on the market are treated with UV light to raise their vitamin D2 content [1]. Ordinary raw portabella mushrooms provide only about 0.1 mcg per half cup, so UV exposure makes a large difference [1]. For people who eat no animal foods, UV-exposed mushrooms and fortified plant milks are the main food options.

Fortified dairy, plant milks and cereals

Fortified foods provide most of the vitamin D in American diets. Almost all U.S. milk is voluntarily fortified with about 3 mcg (120 IU) per cup. Plant milks made from soy, almond or oats are often fortified to a similar level. Cheese and ice cream are usually not fortified. Some brands of orange juice, yogurt and margarine also add vitamin D, so check the Nutrition Facts label [1].

Eggs, liver and other animal foods

Egg yolks, beef liver and cheese contain small amounts of vitamin D3 and a related form called 25-hydroxyvitamin D. The amount depends on what the animal ate [1]. Researchers think the 25-hydroxy form may be more potent than vitamin D3 itself at raising blood levels, so these foods may contribute more than their listed values suggest. The NIH calls this an emerging area of research [1].

How Much Vitamin D Do Adults Need?

The RDAs were set to support bone health and normal calcium metabolism, and they assume minimal sun exposure [1]. One microgram equals 40 IU. National survey data show most Americans eat less than the RDA from food, yet most have adequate blood levels, partly because of sun exposure [1].

A practical day might combine a 3-ounce serving of salmon (about 14 mcg) with a cup of fortified milk or soy milk (about 3 mcg). Without fish, reaching 15 mcg from food alone takes several fortified servings, which is why many people also rely on sun or a supplement.

Sunlight and Vitamin D

When UVB rays reach bare skin, the skin makes vitamin D3. Season, time of day, cloud cover, smog, skin melanin and sunscreen all change how much is made. Older adults and people with darker skin make less, and sunlight through a window does not count, because UVB does not pass through glass [1].

Some experts suggest that about 5 to 30 minutes of midday sun on the face, arms, hands and legs, at least twice a week, usually produces enough vitamin D. The NIH also notes that UV radiation is a cause of skin cancer and that limiting exposure and using sunscreen remains prudent [1]. That is one reason food and supplements matter for many people.

Vitamin D Supplements

Supplements come as vitamin D2 or vitamin D3. Both are well absorbed, but most evidence shows D3 raises and maintains blood levels more than D2 [1]. Because vitamin D is fat soluble, taking it with a meal that contains some fat may help absorption, though some is absorbed without fat [1].

Groups more likely to fall short include older adults, people with little sun exposure, people with darker skin, people who cannot absorb fat well, people with obesity or who have had gastric bypass surgery, and those with milk allergy, lactose intolerance or a vegan diet [1]. A blood test for 25-hydroxyvitamin D is the usual way to check vitamin D status [1].

Multivitamins are one common source. OPA's Women's Daily Multivitamin lists 10 mcg of vitamin D3 per two-capsule serving, along with B vitamins, vitamin C, vitamin E, zinc and magnesium. For comparison, 10 mcg is about two-thirds of the 15 mcg RDA for women up to age 70 and half of the 20 mcg RDA after 70, so food or sun still needs to supply the rest. It is formulated for adult women. For more on pairing vitamin D with vitamin K2, see our guide to vitamin D3 and K2.

Vitamin D and Normal Thyroid Function: What Research Shows

The thyroid makes hormones that help regulate metabolism. Iodine is an essential part of those hormones, T4 and T3, and the pituitary gland controls their release through thyroid-stimulating hormone [2]. If you are reading about nutrition for the thyroid, iodine is the nutrient most directly involved; our article on iodine and thyroid function covers it in detail.

Vitamin D's role is less direct and is still being studied, mainly in connection with the immune system:

• A 2015 meta-analysis of 20 case-control studies found that people with autoimmune thyroid conditions had lower average vitamin D levels than people without them [3]. Studies like these show an association, not cause and effect; low vitamin D could be a consequence of illness rather than a cause.
• A 2021 meta-analysis of 8 small randomized trials (652 people with Hashimoto's thyroiditis) reported that vitamin D supplementation lowered thyroid antibody levels, with large differences between studies [4]. Antibody levels are a lab marker, and the trials did not show effects on thyroid hormone needs or symptoms.
• In the VITAL trial of 25,871 older U.S. adults, 2,000 IU of vitamin D3 a day for about five years was followed by fewer confirmed autoimmune diagnoses overall than placebo (123 vs 155 people) [5]. Autoimmune thyroid disease was counted within that combined total, so the trial does not isolate a thyroid effect.

Taken together, this research is interesting but not settled, and none of it means vitamin D foods or supplements should replace care from a clinician. If you have a thyroid condition, ask your doctor whether checking your vitamin D level makes sense for you.

Easy Ways to Add Vitamin D Foods

• Breakfast: a fortified cereal with fortified milk or soy milk, or scrambled eggs with sautéed UV-exposed mushrooms.
• Lunch: a salad or sandwich with canned salmon, sardines or light tuna.
• Dinner: baked or grilled trout or salmon once or twice a week.
• Shopping: compare Nutrition Facts labels; vitamin D is listed in micrograms, and a food with 20% DV or more is a high source [1].

Safety and Interactions

Vitamin D from sun does not cause toxicity, but supplements can. Too much vitamin D raises blood calcium, which can cause nausea, vomiting, muscle weakness, neuropsychiatric disturbances, pain, loss of appetite, dehydration, excessive urination and thirst, and kidney stones; extreme cases can be dangerous [1]. Adults should stay at or below 100 mcg (4,000 IU) a day from all supplements and fortified foods combined unless a clinician directs otherwise [1]. Taking high-dose calcium with vitamin D may add to the risk of some side effects [1].

Talk to your doctor or pharmacist before taking vitamin D supplements if you take [1]:

• Orlistat (Xenical, alli), which can reduce vitamin D absorption.
• Statins such as atorvastatin, lovastatin or simvastatin; high vitamin D intakes might reduce the potency of some statins.
• Corticosteroids such as prednisone, which can impair vitamin D metabolism.
• Thiazide diuretics, which combined with vitamin D supplements might raise blood calcium too high, especially in older adults.

Also check with your clinician first if you have a kidney, liver or parathyroid condition, or if you are pregnant or breastfeeding.

Frequently Asked Questions

What food is highest in vitamin D?

Cod liver oil is the most concentrated common source, at about 34 mcg per tablespoon. Among whole foods, farmed rainbow trout (16.2 mcg per 3 ounces) and sockeye salmon (14.2 mcg) lead the NIH list, followed by UV-exposed mushrooms (9.2 mcg per half cup) [1].

How much vitamin D do I need each day?

Adults need 15 mcg (600 IU) a day through age 70 and 20 mcg (800 IU) after age 70. These amounts were set for bone health and normal calcium metabolism, not specifically for the thyroid [1].

Does vitamin D support thyroid function?

Vitamin D is studied for its links to immune and thyroid function, and people with some thyroid conditions tend to have lower levels in observational studies [3]. Small trials have measured changes in thyroid antibodies [4], but the evidence is still developing. Iodine is the nutrient thyroid hormones are built from [2].

Can I get enough vitamin D from the sun?

Many people get some of their vitamin D from the sun, but the amount varies with season, time of day, cloud cover, skin tone, age and sunscreen use, and window light does not help. Because UV radiation is a cause of skin cancer, the NIH notes that limiting sun exposure is still prudent [1].

Is it possible to get too much vitamin D?

Yes, from supplements. The adult upper limit is 100 mcg (4,000 IU) a day. Too much can raise blood calcium and cause nausea, weakness and kidney problems. Sun exposure alone does not cause vitamin D toxicity [1].

Do vegetarians and vegans have trouble getting vitamin D?

They can, because most natural sources are animal foods. UV-exposed mushrooms and fortified plant milks and cereals are the main plant-based options, and the NIH lists vegan diets among the situations linked to low intake [1].

Sources

1. NIH Office of Dietary Supplements. Vitamin D: Fact Sheet for Health Professionals.
2. NIH Office of Dietary Supplements. Iodine: Fact Sheet for Health Professionals.
3. Wang J, Lv S, Chen G, et al. Meta-analysis of the association between vitamin D and autoimmune thyroid disease. Nutrients. 2015.
4. Zhang J, Chen Y, Li H, Li H. Effects of vitamin D on thyroid autoimmunity markers in Hashimoto's thyroiditis: systematic review and meta-analysis. Journal of International Medical Research. 2021.
5. Hahn J, Cook NR, Alexander EK, et al. Vitamin D and marine omega 3 fatty acid supplementation and incident autoimmune disease: VITAL randomized controlled trial. BMJ. 2022.

Disclosure: OPA Nutrition sells supplements, including products mentioned in this article. This content is for education only and is not medical advice. Statements about dietary supplements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. Talk to your healthcare provider before using any supplement, especially if you take medication or have a medical condition.

Written and reviewed by Michael Gonzales, Founder, OPA Nutrition · Last reviewed: October 17, 2026 · How OPA researches and writes