title: Iron bioavailability in infants from an infant cereal fortified with ferric pyrophosphate or ferrous fumarate.
abstract: BACKGROUND
  Infant cereals are commonly fortified with insoluble iron compounds with low relative bioavailability, such as ferric pyrophosphate, because of organoleptic changes that occur after addition of water-soluble iron sources.
  
  
  OBJECTIVE
  Our objective was to compare iron bioavailability from ferric pyrophosphate with an alternative iron source that is soluble in dilute acid, ferrous fumarate, and to evaluate the influence of ascorbic acid on iron bioavailability from ferrous fumarate in infants.
  
  
  METHODS
  Iron bioavailability was measured as the incorporation of stable iron isotopes into erythrocytes 14 d after administration of labeled test meals (25 g dry wheat and soy infant cereal, 100 g water, and 2.5 mg Fe as [57Fe]ferric pyrophosphate or [57Fe]ferrous fumarate). Ascorbic acid was added to all test meals (25 mg in study 1 or 25 or 50 mg in study 2). Infants were fed each test meal on 4 consecutive days under standardized conditions. The 2 different test meals within each study were administered 2 wk apart in a crossover design.
  
  
  RESULTS
  Geometric mean iron bioavailability was significantly higher from [57Fe]ferrous fumarate than from [57Fe]ferric pyrophosphate [4.1% (range: 1.7-14.7%) compared with 1.3% (range: 0. 7-2.7%); n = 8, P = 0.008]. In this study, doubling the ascorbic acid content did not further enhance iron bioavailability; the geometric means (range) were 3.4% (1.9-6.6%) and 4.2% (1.2-18.7%) for the test meals with 25 and 50 mg ascorbic acid added, respectively (n = 9).
  
  
  CONCLUSIONS
  Iron bioavailability from iron-fortified infant cereals can be improved by using an iron compound with high relative bioavailability and by ensuring adequate ascorbic acid content of the product.
authors.affiliation: Laboratory for Human Nutrition, Institute of Food Science, Swiss Federal Institute of Technology, R]uschlikon, Switzerland. davidsson@ilw.agrl.ethz.ch
authors.forename: L
authors.initials: L
authors.lastname: Davidsson
authors.forename: P
authors.initials: P
authors.lastname: Kastenmayer
authors.forename: H
authors.initials: H
authors.lastname: Szajewska
authors.forename: R F
authors.initials: RF
authors.lastname: Hurrell
authors.forename: D
authors.initials: D
authors.lastname: Barclay
mesh_terms: D001682:Biological Availability; D011756:Diphosphates / Q000008:administration & dosage*; D002523:Edible Grain; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D005296:Ferrous Compounds / Q000008:administration & dosage*; D005527:Food, Fortified; D006801:Humans; D007223:Infant; D007225:Infant Food; D007501:Iron / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics*; D007503:Iron Isotopes; D008297:Male; D013025:Glycine max; D014908:Triticum
chemical_list: D011756:Diphosphates; D005296:Ferrous Compounds; D007503:Iron Isotopes; D007501:Iron; C049051:ferric pyrophosphate; C031621:ferrous fumarate