What Does Vitamin D Do?
What does vitamin D do? Osteoporosis Canada reports that vitamin D3 can increase calcium absorption by as much as 30 to 80 percent... an important consideration for osteoporosis prevention and treatment.
The major function of Vitamin D is to maintain normal blood levels of calcium and phosphorus. It is best known for helping the body to absorb calcium into the bones, improving bone density and preventing osteoporosis. Research also suggests that vitamin D may provide protection from hypertension (high blood pressure), cancer, and several autoimmune diseases.
Vitamin D is known as the “sunshine vitamin” and is formed naturally by the body when exposed to the sun. As little as 10 minutes of exposure is thought to be enough to prevent deficiencies... if a person is living south of the 42 latitude (below Boston or Rome). Vitamin D is also found in many dietary sources such as fish, eggs, fortified milk and cod liver oil. But aside from cod liver oil, few foods high in vitamin D provide enough of the vitamin to reach the recommended levels in our blood.
There are several different forms of vitamin D. Vitamin D2 (ergocalciferol) is synthesized by plants while Vitamin D3 (cholecalciferol) is synthesized by our skin when we are exposed to ultraviolet-B (UVB) rays from sunlight. While most vitamin supplements and dairy products are fortified with D3, some orange juices and soymilks are fortified with D2 which research suggests is less effective than D3.