Vitamin D shine bitamin kuma shima hormone ne na steroid, galibi ya haɗa da VD2 da VD3, waɗanda tsarin su yayi kama da juna. Ana canza Vitamin D3 da D2 zuwa 25 hydroxyl bitamin D (ciki har da 25-dihydroxyl bitamin D3 da D2). 25- (OH) VD a cikin jikin mutum, tsayayyen tsari, babban taro. 25- (OH) VD yana nuna jimlar adadin bitamin D, da ikon canzawa na bitamin D, don haka 25- (OH) VD yana dauke da mafi kyawun alama don kimanta matakin bitamin D. Kit ɗin Diagnostic ya dogara ne akan Immunochromatography kuma zai iya ba da sakamako a cikin mintuna 15.