Cholecalciferol is actually an alias for vitamin D3, which is a type of vitamin D. It is a fat-soluble vitamin that is very important for the regulation of human physiological functions. Vitamin D is a fat-soluble vitamin that plays a major role in calcium and phosphorus metabolism and can promote calcium absorption, thus preventing osteoporosis. In addition, because of the promotion of calcium absorption, calcium, in addition to the growth of bone has a very important role in the regulation of the nervous system and the function of the immune system, but also has a very important effect. Therefore, calcium supplementation is very important for the regulation of the whole life. Vitamin D is what promotes calcium absorption and is therefore also very important for the body’s vital functions. In short, cholecalciferol, generally referred to as vitamin D, promotes the absorption of calcium and phosphorus by the body, keeps blood calcium and blood phosphorus in relative balance, can promote growth and calcification of bones, and promotes sound teeth. In addition, to the intestinal wall can also increase the absorption of phosphorus, and through the renal tubules to increase the reabsorption of phosphorus, can maintain the normal level of citrate in the blood, and can prevent the loss of amino acids through the kidneys, and to the nervous system, as well as the skeletal-muscular system, have a very important role in regulating.