25 OH Vitamin D Total ( 1 )
Vitamins am vital amines needed the body for maintaining good health. There are various types of vitamins viz. A, B. C, Dr E & K. Of these, vitamin B complex and C are water soluble while vitamins A, D, i and K are fat soluble. Vitamin D includes many subfamilies, however from clinical perspective, estimation of VITD2 and VITD3 are important.
Vitamin D2, also known as ergocalciferol is synthesized by plants, fungi and bacteria upon exposure to the UVB rays in sunlight, while vitamin D3, also known as cholecalciferol is found in animals.
Vitamin D3 is generally present at higher concentrations in the human body, as is the major contributor for total vitamin D levels in human serum ami is synthesized in the humans on exposure to sunlight. Many routine food products are considered as a rich source of vitamin D3 like milk, fish, egg and cod liver oil. Vitamin D3 is also more stable as compared to vitamin D2, because it binds to the vitamin D receptors (VDR) with a very high affinity