What is Vitamin D3?
Vitamin D3 is a form of Vitamin D which is usually produced in the skin of animals and humans after exposure to sunlight. Also called cholecalciferol, some natural forms of this vitamin can be found in some foods. Vitamin D2 meanwhile is the other form of vitamin D called ergocalciferol and is commonly found in plant or fungi.

Vitamin D in general is considered a fat-soluble secosteroid. But since it is produced by the body, some experts refer to it as a hormone. This particular vitamin also plays a big role in the body’s function to produce calcium and phosphorus. Vitamin D3 is also important in calcium absorption. Because of this action, Vitamin D3 is given as a supplement for those who want to build stronger and healthier bones. But aside from its effect on the absorption of calcium in the body’s bones, Vitamin D3 is also said to help boost the body’s immune system and may also help in the reduction of inflammation.

When human and animal skin is exposed to sunlight, particularly UVB rays, a bodily substance called 7-dehydrocalciferol is converted into Vitamin D3. But aside from the effect of sunlight on Vitamin D3 production in the skin, some food items contain natural forms of this vitamin. Foods rich in Vitamin D3 include fish (like salmon and tuna), fish liver oils, cheese, beef liver, and egg yolks. But since most natural forms of this particular vitamin are in small quantities only, many food items are now fortified with Vitamin D3. Examples of fortified food items are fruit juices, yogurt, and cereals among others.

When there is not enough of Vitamin D3 circulating in the body, calcium absorption will be impaired. This will lead to conditions such as rickets and osteoporosis, with both referring to unhealthy and brittle bones. In many instances, doctors prescribe supplementation to combat the ill-effects of Vitamin D3 efficiency.