BIOMOLECULES AND ENZYMES

Detailed explanation-1: -The body needs vitamin D to absorb calcium. Without enough vitamin D, one can’t form enough of the hormone calcitriol (known as the “active vitamin D”). This in turn leads to insufficient calcium absorption from the diet.

Detailed explanation-2: -The principal function of vitamin D in calcium homeostasis is to increase calcium absorption from the intestine. Calcium is absorbed by both an active transcellular pathway, which is energy dependent, and by a passive paracellular pathway through tight junctions.

Detailed explanation-3: -The two forms of vitamin D in supplements are D2 (ergocalciferol) and D3 (cholecalciferol). Both forms increase vitamin D in your blood, but D3 might raise it higher and for longer than D2. Because vitamin D is fat-soluble, it is best absorbed when taken with a meal or snack that includes some fat.