Vitamin D health effects

For a long time, scientists thought of Vitamin D mostly as a regulator of calcium and bone health. Which is true, as far as it goes: in fact it was cod liver oil curing kids with rickets in the early 20th century that led to its discovery and mistaken identity as a vitamin.
Since that time, other crucial functions of Vitamin D have been discovered, and as of this writing(2010), the growth of knowledge of and interest in Vitamin D seems to be accelerating. Vitamin D deficiency has been linked to hypertension, heart disease, insulin resistance and diabetes, cancer, depression, multiple sclerosis, and chronic pain, just to name a few.