Vitamin D is a fat soluble steroid hormone precursor that contributes to the maintenance of normal levels of calcium in the blood stream by increasing absorption of calcium from food and reducing urinary calcium loss (reabsorption by the kidneys).
Both effects keep calcium in the body and therefore spare the calcium that is stored in bones. When necessary, vitamin D transfers calcium from the bone into the bloodstream, which does not benefit bones.
The bones grow denser and stronger as they absorb and deposit the calcium.
Although the overall effect of vitamin D on the bones is complicated, some vitamin D is necessary for healthy bones and teeth.
Therefore, vitamin D prevent muscle aches, bone pains, chronic fatigue and osteoporosis.
Vitamin D plays a vital role in the normal functioning of the immune system and blood cell formation and also helps cells "differentiate"—a process that may reduce the risk of cancer.
From animal and human studies, researchers have hypothesized that vitamin D may protect people from tuberculosis, gum inflammation, multiple sclerosis, autoimmune arthritis, and juvenile diabetes.
Vitamin D controls the growth of normal as well as cancerous cells. It is important role in the prevention of various cancer especially cancer of the colon, prostate pancreas and breast.
Vitamin D is also needed for adequate blood levels of insulin. It stimulates the production of insulin form insulin producing cells in the pancreas.
Vitamin D isn’t actually a vitamin Vitamin D produced by the body. When the skin exposed to ultra Violet B radiation from sun, vitamin D is synthesized.
This fat soluble vitamin is transported to the liver and kidneys and become activated vitamin D.
Roles of Vitamin D in Our Body