title: Acute copper supplementation does not inhibit non-heme iron bioavailability in humans.
abstract: To measure the effect of acute copper (Cu) administration, given as an aqueous solution, on the absorption of iron (Fe), 29 healthy adult women participated in two iron absorption studies. Subjects received 0.5 mg of Fe, as ferrous sulfate, alone or with Cu, as copper sulfate, at 0.5:1, 1:1, or 2:1 Cu/Fe molar ratios (study I) or at 4:1, 6:1, or 8:1 Cu/Fe molar ratios (study II) as an aqueous solution on days 1, 2, 14, and 15 of the study. Fe absorption was assessed by erythrocyte incorporation of iron radioisotopes (55)Fe and (59)Fe. Geometric mean (range +/- SD) absorption of Fe alone or at 0.5:1, 1:1, 2:1 Cu/Fe molar ratios were 34.4% (17.3-68.5%), 40.9% (24.9-67.2%), 48.3% (24.8-94.1%), and 50.2% (25.3-99.5%), respectively (ANOVA, p = 0.12). Geometric mean (range +/- SD) absorption of Fe alone or at 4:1, 6:1, 8:1 Cu/Fe molar ratios were 28.7% (12.1-67.9%), 21.5% (6.5-71.5%), 29.6% (10.3-85.4%), and 36.5% (18.3-73.1%), respectively (ANOVA, p = 0.16). In conclusion, combined Cu and Fe administration in an aqueous solution does not inhibit Fe bioavailability. This information could help in the design of rational guidelines for copper and iron supplementation programs. Our results support the hypothesis that divalent metal transporter 1 is not physiologically relevant for copper absorption in humans.
authors.affiliation: Institute of Nutrition and Food Technology, University of Chile, Santiago, Chile. molivare@inta.cl
authors.forename: Manuel
authors.initials: M
authors.lastname: Olivares
authors.forename: Fernando
authors.initials: F
authors.lastname: Pizarro
authors.forename: Daniel
authors.initials: D
authors.lastname: López de Romaña
authors.forename: Manuel
authors.initials: M
authors.lastname: Ruz
mesh_terms: D000328:Adult; D001682:Biological Availability; D019327:Copper Sulfate / Q000008:administration & dosage / Q000493:pharmacokinetics*; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D005260:Female; D005296:Ferrous Compounds / Q000008:administration & dosage / Q000493:pharmacokinetics*; D006801:Humans
chemical_list: D005296:Ferrous Compounds; C020748:ferrous sulfate; D019327:Copper Sulfate