Answer: Vitamin D3, cholecalciferol, is formed when skin is exposed to the sun’s rays. Vitamin D2, ergocalciferol, is formed, or synthesized, by plants. Foods are fortified with one or the other. Many professionals recommend a vitamin D3 supplement because it is thought to be more potent and useful. Others recommend either form because vitamin D2 has been used for a long time. Vitamin D3 is generally not considered vegan.
Eggs, fortified milk and cereals, salmon, cod, and cod liver oil, are considered major sources of this important vitamin. Supplements are also considered a major, and often necessary, source.
The sun is an excellent source and ten minutes of non-peak exposure every few days is said to be enough to prevent vitamin D deficiency. Some say two to three times a week. The exposure need not be on the face. Arms and legs do a great job of absorbing rays. Although sunscreen is highly recommended, these particular ten minutes are ideally spent with no sunscreen or sunblock. Exposure time need increases for those who live in Northern climates. It also increases for those with dark skin. The darker the skin, the longer the exposure. Another barrier is age. As the body ages, it processes Vitamin D less efficiently.
Vitamin D is categorized as a fat soluble vitamin but it is also, and some say should have been called, a “pre-hormone”. One good reason to include healthy fats in a daily diet. The body stores it, which is why it is important not to overdo supplementation. It is said to play a role in calcium absorption, maintaining healthy calcium and phosphorus blood levels, healthy blood pressure, a healthy immune system, and protection against osteoporosis, asthma, depression, and possibly cancer.
Vitamin D blood levels can be checked and, based on results, a health professional can recommend an appropriate supplement. In the meantime, a generally accepted daily supplement level would be anywhere from 800 to 1000 IU.
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