Calcifediol
![Skeletal formula of calcifediol](/Images/godic/202501/02/Calcidiol2.svg5657.png")
![Ball-and-stick model of the calcifediol molecule](/Images/godic/202501/02/Calcifediol_3D_ball5657.png")
![[[File:
[[<div style=](/Images/godic/202501/02/VitaminDSynthesis_WP15315657.png")
Calcifediol (INN), also known as calcidiol, 25-hydroxycholecalciferol, or 25-hydroxyvitamin D (abbreviated 25(OH)D), is a prehormone that is produced in the liver by hydroxylation of vitamin D3 (cholecalciferol) by the enzyme cholecalciferol 25-hydroxylase which was isolated by Michael F. Holick. Physicians worldwide measure this metabolite to determine a patient's vitamin D status. At a typical daily intake of vitamin D3, its full conversion to calcifediol takes approximately 7 days.