title: Effects of vitamin D3 and calcium supplementation on serum levels of tocopherols, retinol, and specific vitamin D metabolites.
abstract: γ-Tocopherol (γT) protects against DNA-damaging effects of nitrogen oxides, yet its physiologic regulation in vivo is unknown. Observational studies indicate inverse associations of 25[OH]-vitamin D with γT and leptin. To determine whether vitamin D(3) supplementation alters levels of lipid-soluble micronutrients, serum samples (N = 85 subjects) from a randomized, double-blind, placebo-controlled clinical trial of vitamin D(3) (800 IU) and calcium (2 g), alone and in combination, were analyzed for lipid micronutrients and specific vitamin D metabolites at baseline and after 6 mo of supplementation. Serum 25[OH]-vitamin D(3) levels increased 55% (P < 0.0001) and 48% (P = 0.0005), whereas 25[OH]-vitamin D(2) levels were lower by 48% (P = 0.26) and 21% (P = 0.36) in the vitamin D(3) and vitamin D(3) plus calcium groups, respectively. At baseline, γT levels were inversely associated with 25[OH]D (r = -0.31, P = 0.004). With vitamin D(3) plus calcium treatment, serum α-tocopherol decreased 14% (P = 0.04), whereas similar changes in γT (19% lower, P = 0.14) were observed. No significant effects were observed for D(3) supplementation on leptin or retinol levels. These results are consistent with the hypothesis that vitamin D(3) ± calcium affects serum tocopherol and 25[OH]D(2) levels; however, studies using larger, more homogeneous populations are warranted.
authors.affiliation: Epidemiology Program, Cancer Research Center of Hawaii, University of Hawaii, Honolulu, Hawaii 96822, USA.
authors.forename: Weiwen
authors.initials: W
authors.lastname: Chai
authors.forename: Roberd M
authors.initials: RM
authors.lastname: Bostick
authors.forename: Thomas U
authors.initials: TU
authors.lastname: Ahearn
authors.forename: Adrian A
authors.initials: AA
authors.lastname: Franke
authors.forename: Laurie J
authors.initials: LJ
authors.lastname: Custer
authors.forename: Robert V
authors.initials: RV
authors.lastname: Cooney
mesh_terms: D015652:25-Hydroxyvitamin D 2 / Q000097:blood; D000328:Adult; D000368:Aged; D002112:Calcifediol / Q000097:blood; D002118:Calcium / Q000097:blood; D002136:Calcium, Dietary / Q000494:pharmacology*; D002762:Cholecalciferol / Q000494:pharmacology*; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D020738:Leptin / Q000097:blood; D008297:Male; D008875:Middle Aged; D024505:Tocopherols / Q000097:blood*; D014801:Vitamin A / Q000097:blood*; D024504:gamma-Tocopherol / Q000097:blood
chemical_list: D002136:Calcium, Dietary; D020738:Leptin; D014801:Vitamin A; D002762:Cholecalciferol; D015652:25-Hydroxyvitamin D 2; D024504:gamma-Tocopherol; D002112:Calcifediol; D024505:Tocopherols; D002118:Calcium