Vitamin D
6
Natural sources of vitamin D include:
Natural sources
* A whole egg, provides 20 IU (0.33 IU/g if egg weighs 60 g)
* Beef liver, cooked, 100 g (3.5 oz), provides 15 IU (0.15 IU/g)
* Fish liver oils, such as cod liver oil, 1 Tbs. (15 ml) provides 1360 IU (90.6 IU/ml)
* Mushrooms are the only vegan source of vitamin D (besides UV light or sunlight exposure). Nutrition Facts labels on food products in the US are not required to list vitamin D content unless a food has been fortified with this nutrient. In many countries, such foods as milk, yogurt, margarine, oil spreads, breakfast cereal, pastries, and bread are fortified with vitamin D2 and/or vitamin D3. In the United States and Canada, for example, fortified milk typically is labeled as providing 100 IU per cup (1 IU is the biological equivalent of 0.025 μg). Laboratory analysis of milk products sold in the US shows that the actual vitamin D content is often much less than stated on the label. European milk was also at one time fortified with vitamin D but too much was used; the toxic effects on children led to public outrage and European governments banned vitamin D fortification of milk in the 1950s. Multivitamin tablets commonly contain approximately 100% of the minimum recommended daily value (e.g. 500 IU). Vitamin D tablets and softgel capsules with 1000, 2000 or 5000 IU are available without prescription in the US. Vitamin D in supplements is available in two forms, D2 (ergocalciferol) and D3 (cholecalciferol). Vitamin D2 is manufactured by the UV irradiation of ergosterol in yeast, and vitamin D3 is manufactured by the irradiation of 7-dehydrocholesterol from lanolin and the chemical conversion of cholesterol. The two forms were traditionally regarded as equivalent based on their
Artificial sources