جدول الأطعمة الغنية بفيتامين د

Vitamin D is unusual among nutrients in that food is the secondary source for most people; skin synthesis from sunlight normally supplies more. That makes the food chart most relevant precisely when sunlight is not available, in winter at high latitude, for people who cover their skin, and for anyone with darker skin, in whom melanin substantially slows cutaneous synthesis.

How much vitamin D you need

Recommendations are given in both micrograms and International Units, and the two appear interchangeably on labels, which is a frequent source of confusion. One microgram equals 40 IU.

• Breastfed infants need a supplement, because breast milk contains very little vitamin D regardless of the mother intake.
• The upper limit is a genuine ceiling. Vitamin D is fat soluble and accumulates, and toxicity from high-dose supplements causes hypercalcaemia.

Vitamin D per realistic serving

Calculated from USDA FoodData Central per-100-gram values scaled to the portions shown, with IU conversions at 40 IU per microgram.

• Ordinary mushrooms contain very little vitamin D. Only those deliberately exposed to ultraviolet light carry the amounts shown, and the packaging says so.
• Oily fish is the only unfortified food group that reliably supplies a large share of a day requirement in one serving.

Sunlight, skin and why deficiency is common

Ultraviolet B radiation converts a cholesterol precursor in skin to vitamin D3. The efficiency of that reaction depends on latitude, season, time of day, skin pigmentation, age and sunscreen use. Above roughly 37 degrees latitude, winter sunlight contains too little UVB for meaningful synthesis for several months a year, which is why intake from food and supplements matters most in exactly the months when people are least likely to think about it.

Melanin absorbs UVB, so people with darker skin need considerably longer exposure to produce the same amount, and are correspondingly more likely to have low vitamin D status at a given latitude. Age matters too: skin synthesis capacity declines substantially over the decades, which is part of why the recommendation rises after 70.

حدود الاستخدام

• Fortification levels vary by country and by product. The milk, juice and cereal figures above are for specific US records and do not transfer to other markets.
• Vitamin D content in fish varies with species, whether the fish is farmed or wild, and with fat content, so the figures are representative rather than exact.
• Only UV-exposed mushrooms contain meaningful vitamin D. Standard cultivated mushrooms contain very little.
• Food alone rarely meets requirements without oily fish or fortified products, which is why supplementation is commonly advised in winter at high latitudes.
• Serum 25-hydroxyvitamin D reflects total exposure from sun, food and supplements together, so dietary intake alone does not predict status.
• High-dose supplementation can cause toxicity. The upper limits above apply to total intake from all supplement sources.

الأسئلة الشائعة

How much vitamin D do I need per day?

15 mcg (600 IU) for most people aged 1 to 70, rising to 20 mcg (800 IU) after 70, with an Adequate Intake of 10 mcg (400 IU) for infants. The tolerable upper limit for adults is 100 mcg (4,000 IU) a day.

Which foods are highest in vitamin D?

UV-exposed mushrooms and oily fish. A cup of UV-exposed portabella supplies about 977 IU and a 3 oz serving of canned sockeye salmon about 714 IU, well above a day requirement in a single serving.

Can I get enough vitamin D from sunlight alone?

In summer at moderate latitudes, often yes. Above roughly 37 degrees latitude, winter sunlight contains too little UVB for meaningful synthesis for several months, and skin pigmentation, age and sunscreen all reduce it further.

Do mushrooms really contain vitamin D?

Only if they have been exposed to ultraviolet light, which some growers do deliberately and label accordingly. Ordinary cultivated mushrooms contain very little.

What is the difference between mcg and IU?

They are two units for the same thing. One microgram of vitamin D equals 40 IU, so 15 mcg is 600 IU. Labels use both, which is a common source of confusion when comparing products.

المراجع

1. USDA FoodData Central. Food composition database, values pulled 2026-08-25.
2. NIH Office of Dietary Supplements. Vitamin D Fact Sheet for Health Professionals.
3. National Academies. Dietary Reference Intakes for Calcium and Vitamin D. NCBI Bookshelf.
4. MedlinePlus. Vitamin D.