Vitamin D, a type of fat-soluble vitamin, comprises five categories identified as 2–6. The main variants are cholecalciferol, also known as vitamin D3, and ergocalciferol, also known as vitamin D2. They have structural differences primarily in the side chain; vitamin D2 has a C22–C23 double bond and an extra methyl group at C24 [1]. Plants and fungi produce vitamin D2 from ergosterol, whereas human skin synthesizes vitamin D3 from 7-dehydrocholesterol (7-DHC) when exposed to UVB radiation [2]. A photochemical reaction initiated by UV photons transforms 7-DHC into previtamin D3, subsequently converting to vitamin D3 through thermal isomerizations [3]. Vitamin D3 is carried in the bloodstream by Vitamin D binding protein (DBP) to the liver, where it undergoes conversion by CYP2R1 to 25-hydroxyvitamin D3 [25(OH)D3], which is the main circulating form of vitamin D3. In the kidneys, CYP27B1 transforms 25(OH)D3 into its active state, known as 1,25-dihydroxyvitamin D3 [1,25(OH)2D3].