25-hydroxy Calcifediol, also known medically as cholecalciferol, is very similar to vitamin D3 by the addition of a hydroxyl group to the 25-position carbon atoms of vitamin D3, which is carried out by a series of biochemical reactions in the body, 25-hydroxy Calcifediol is achieved by the hydroxylation of the 25-hydroxylase enzyme in the mitochondria of the hepatocytes. So what are the differences between 25-hydroxy Calcifediol and vitamin D3?
Vitamin D3 is a precursor to active metabolites and is not biologically active, while 25-Hydroxy Calcifediol is a biologically active substance. In the human body, 25-hydroxy Calcifediol is stored in the liver, while vitamin D3 is stored in the liver, fat, plasma, and muscle. 25-Hydroxy Calcifediol is more easily absorbed than vitamin D3 and can be absorbed directly from the intestine into the bloodstream. In terms of absorption, 25-Hydroxy Calcifediol is more efficient than vitamin D3, bypassing the liver for faster and more efficient conversion. 25-Hydroxy Calcifediol is a short metabolic process that accelerates the absorption of calcium.