title: Plasma zinc concentration increases within 2 weeks in healthy Senegalese men given liquid supplemental zinc, but not zinc-fortified wheat bread.
abstract: The responsiveness of plasma zinc concentration to zinc fortification is uncertain. Our objective in this study was to determine whether plasma zinc concentration changes in response to consuming zinc-fortified foods or liquid zinc supplements. We conducted a 4-wk double-blind, randomized trial among 132 healthy Senegalese men ≥ 18 y. Participants received 1 of 4 interventions: 1) (control) 200 g/d of wheat bread fortified with iron and folic acid, but not zinc, and a liquid multivitamin supplement without zinc between meals; 2) (zinc supplement) the same bread and the same multivitamin supplement with 15 mg zinc as ZnSO(4) added; 3) (moderate zinc fortification) the same bread cofortified with 7.5 mg zinc as ZnO and the same multivitamin supplement without zinc; or 4) (high zinc fortification) the same bread cofortified with 15 mg zinc as ZnO and the same multivitamin supplement without zinc. Fasting blood samples were collected twice at baseline and at d 15 and 29 of the intervention. There was no significant interaction between group and study day (P = 0.11). However, at d 15, the mean change in plasma zinc concentration in the zinc-supplemented group was greater than in the placebo and fortification groups ( 0.72 μmol/L vs. -0.09 to 0.03 μmol/L; P = 0.05). At d 29 there were no significant group-wise differences. Across all time points, the zinc-supplemented group was the only group where plasma zinc concentration increased from baseline (P = 0.006). These results suggest that plasma zinc concentration may not be a sufficiently sensitive indicator to evaluate short-term responses to zinc fortification.
authors.affiliation: Program in International and Community Nutrition, and Department of Nutrition, University of California, Davis, CA 95616, USA.
authors.forename: Grant J
authors.initials: GJ
authors.lastname: Aaron
authors.forename: Nafissatou
authors.initials: N
authors.lastname: Ba Lo
authors.forename: Sonja Y
authors.initials: SY
authors.lastname: Hess
authors.forename: Amadou T
authors.initials: AT
authors.lastname: Guiro
authors.forename: Salimata
authors.initials: S
authors.lastname: Wade
authors.forename: Kenneth H
authors.initials: KH
authors.lastname: Brown
mesh_terms: D000293:Adolescent; D000328:Adult; D001939:Bread; D019587:Dietary Supplements; D004311:Double-Blind Method; D005527:Food, Fortified; D006801:Humans; D008297:Male; D012675:Senegal; D013997:Time Factors; D014908:Triticum; D055815:Young Adult; D015032:Zinc / Q000008:administration & dosage* / Q000097:blood*
chemical_list: D015032:Zinc