title: Effect of zinc sulfate fortificant on iron absorption from low extraction wheat flour co-fortified with ferrous sulfate.
abstract: The co-fortification of wheat flour with iron (Fe) and zinc (Zn) is a strategy used to prevent these deficiencies in the population. Given that Zn could interact negatively with Fe, the objective was to assess the effect of Zn on Fe absorption from bread prepared with wheat flour fortified with Fe and graded levels of Zn fortificant. Twelve women aged 30-43 years, with contraception and a negative pregnancy test, participated in the study. They received on four different days, after an overnight fast, 100 g of bread made with wheat flour (70 % extraction) fortified with 30 mg Fe/kg as ferrous sulfate (A) or prepared with the same Fe-fortified flour but with graded levels of Zn, as zinc sulfate: 30 mg/kg (B), 60 mg/kg (C), or 90 mg/kg (D). Fe radioisotopes ((59)Fe and (55)Fe) of high specific activity were used as tracers and Fe absorption iron was measured by the incorporation of radioactive Fe into erythrocytes.
  
  
  RESULTS
  The geometric mean and range of ± 1 SD of Fe absorption were: A= 19.8 % (10.5-37.2 %), B = 18.5 % (10.2-33.4 %), C = 17.7 % (7.7-38.7 %), and D = 11.2 % (6.2-20.3 %), respectively; ANOVA for repeated measures F = 5.14, p < 0.01 (Scheffè's post hoc test: A vs D and B vs D, p < 0.05). We can conclude that Fe is well absorbed from low extraction flour fortified with 30 mg/kg of Fe, as ferrous sulfate, and up to 60 mg/kg of Zn, as Zn sulfate. A statistically significant reduction of Fe absorption was observed at a Zn fortification level of 90 mg Zn/kg.
authors.affiliation: Institute of Nutrition and Food Technology, University of Chile, Santiago, Chile. molivare@inta.uchile.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
mesh_terms: D000042:Absorption; D000328:Adult; D005260:Female; D005296:Ferrous Compounds / Q000737:chemistry*; D005433:Flour / Q000032:analysis*; D005527:Food, Fortified; D006801:Humans; D007501:Iron / Q000737:chemistry*; D008875:Middle Aged; D014908:Triticum / Q000737:chemistry*; D019287:Zinc Sulfate / Q000737:chemistry*
chemical_list: D005296:Ferrous Compounds; C020748:ferrous sulfate; D019287:Zinc Sulfate; D007501:Iron