Also Known as: Cholecalciferol
Vitamin D, also known as Cholecalciferol, is a fat soluble vitamin often referred to as the sunshine vitamin because the ultraviolet B rays of the sun causes skin oils to produce it. But, once the body has reached its required levels of Vitamin D, it simply stops production and conversion of this vitamin. Along with being a proven benefit to strong teeth and bones, Vitamin D has gained reputation most recently as the “rock star” of vitamins for its newly-discovered indications for treating Parkinson’s disease, heart disease, breast cancer and a number of other women’s cancers.
The major function of Vitamin D in humans is to maintain appropriate serum calcium concentrations by enhancing the ability of the small intestine to absorb calcium from the diet. Vitamin D also plays a role in enhancing absorption of phosphorus from the diet.
Vitamin D maintains the blood calcium at supersaturating levels such that it is deposited in the bone as calcium hydroxyapatite.
Vitamin D occurs in two forms. One is produced by the action of sunlight on skin, and the other is found in a limited range of foods and supplements. With current food supplies and patterns of eating, it is almost impossible to obtain sufficient vitamin D from the diet alone. Vitamin D in foods is fat-soluble and is biologically less active.
Deficiency of Vitamin D results in inadequate mineralisation or demineralisation of the skeleton. This can lead to rickets in young children, causing bowed legs and knocked knees.
Vitamin D is also thought to play a role in maintaining the immune system and helping maintain healthy skin and muscle strength.