Cholecalciferol (English: Cholecalciferol, also known as vitamin D3 or cholecalciferol) is a kind of vitamin D.
7-dehydrocholesterol produced by dehydrogenation of cholesterol can form cholecalciferol by ultraviolet irradiation,
so that is It is said that the vitamin D of cholecalciferol is 7-dehydrocholesterol. Cholecalciferol is hydrolyzed in the
liver to form 25-hydroxycholecalciferol, which is then hydroxylated to 1,25-dihydroxycholecalciferol in the kidney.
This substance is 50% more active than cholecalciferol. It has been proven to be a truly active form of vitamin D in the body.
And 1,25-dihydroxycholecalciferol is a hormone secreted by the kidney, so in fact cholecalciferol is also a prohormone.
At the same time, vitamin D is a fat-soluble vitamin, also seen as a hormone precursor acting on calcium and phosphorus metabolism.
It is closely related to sunlight, so it is also called "sunshine vitamin".
Vitamin D3 has the following physiological functions:
1. Increase the absorption of calcium and phosphorus by the body, so that the levels of plasma calcium and plasma phosphorus are saturated.
2, promote growth and bone calcification, promote the integrity of the teeth;
3, increase the absorption of phosphorus through the intestinal wall, and increase the reabsorption of phosphorus through the renal tubule;
4, maintain the normal level of citrate in the blood;
5, prevent amino acids through the kidneys loss.