Hydroxylation25-Hydroxyvitamin D3 1-alpha-Hydroxylase25-Hydroxyvitamin D 2CalcifediolVitamin DVitamin D DeficiencyCholecalciferolSteroid HydroxylasesHydroxycholecalciferolsDihydroxycholecalciferolsErgocalciferols24,25-Dihydroxyvitamin D 3Cytochrome P-450 Enzyme SystemCholestanetriol 26-MonooxygenaseMixed Function OxygenasesParathyroid HormoneCalcitriolVitamin D-Binding ProteinRicketsMicrosomes, LiverSunlightReceptors, CalcitriolProcollagen-Proline DioxygenaseSeasonsDietary SupplementsVitaminsAryl Hydrocarbon HydroxylasesChromatography, High Pressure LiquidSteroid 16-alpha-HydroxylaseBiotransformationOsteomalaciaPhosphorusCalcium, DietaryDebrisoquinKineticsMephenytoinMass SpectrometryCalciumBone DensityCytochrome P-450 CYP3ADealkylationSubstrate SpecificityOxidoreductases, N-DemethylatingBone and BonesCross-Sectional StudiesKidneyHydroxylysineNutritional StatusAdrenodoxinNADPH-Ferrihemoprotein ReductaseSkin PigmentationChromatography, LiquidOxygenasesGas Chromatography-Mass SpectrometryRisk FactorsCholestenesBenzopyrene HydroxylaseMicrosomesLinear ModelsSpectrophotometry, UltravioletTandem Mass SpectrometryBiological MarkersProspective StudiesBone Density Conservation AgentsCytochrome P-450 CYP1A2Cytochrome P-450 CYP2D6Ferredoxin-NADP ReductaseOxidation-ReductionHypoxia-Inducible Factor-Proline DioxygenasesCatalysisCholestanesProlinePhenylalanine HydroxylaseEstrogens, CatecholBenzoflavonesChlorzoxazoneCase-Control StudiesLauric AcidsDietTroleandomycinStereoisomerismProcollagen-Lysine, 2-Oxoglutarate 5-DioxygenaseFood, FortifiedEuropean Continental Ancestry GroupMolecular StructureKetoglutaric AcidsRecombinant ProteinsHydroxybenzoatesSulfaphenazoleNADPMolecular Sequence DataPhenobarbitalPrevalencePhosphatesHypoparathyroidismCohort StudiesDehydrocholesterolsCholestanolsHydroxyprolineLiver