title: In vitro assessment of iron availability from commercial Young Child Formulae supplemented with prebiotics.
abstract: OBJECTIVE
  Iron is essential for development and growth in young children; unfortunately, iron deficiency (ID) is a significant public health problem in this population. Young Child Formulae (YCF), milk-derived products fortified with iron and ascorbic acid (AA, an enhancer of iron absorption) may be good sources of iron to help prevent ID. Furthermore, some YCF are supplemented with prebiotics, non-digestible carbohydrates suggested to enhance iron bioavailability. The aim of our study was to evaluate iron bioavailability of YCF relative to prebiotic and AA concentrations. We hypothesised that YCF with the highest levels of prebiotics and AA would have the most bioavailable iron.
  
  
  METHODS
  We used the in vitro digestion/Caco-2 cell model to measure iron bioavailability from 4 commercially available YCF with approximately equal amounts of iron, but varying amounts of: AA and the prebiotics fructo- and galacto-oligosaccharides. Caco-2 cell ferritin formation was used as a surrogate marker for iron bioavailability.
  
  
  RESULTS
  The YCF with the highest concentration of prebiotics and AA had the highest iron bioavailability; conversely, the YCF with the lowest concentration of prebiotics and AA had the lowest. After the addition of exogenous prebiotics, so that all tested YCF had equivalent amounts, there was no longer a significant difference between YCF iron bioavailability.
  
  
  CONCLUSIONS
  Our results suggest that ascorbic acid and prebiotics in YCF improve iron bioavailability. Ensuring that iron is delivered in a bioavailable form would improve the nutritional benefits of YCF in relation to ID/IDA amongst young children; therefore, further exploration of our findings in vivo is warranted.
authors.affiliation: Department of Life and Sports Sciences, Faculty of Engineering and Science, University of Greenwich, Medway Campus, Chatham Maritime, Kent, ME4 4TB, UK. T.Christides@gre.ac.uk.
authors.forename: Tatiana
authors.identifier: http://orcid.org/0000-0002-3160-4857
authors.initials: T
authors.lastname: Christides
authors.affiliation: Department of Life and Sports Sciences, Faculty of Engineering and Science, University of Greenwich, Medway Campus, Chatham Maritime, Kent, ME4 4TB, UK.
authors.forename: Julia Clark
authors.initials: JC
authors.lastname: Ganis
authors.affiliation: Metal Metabolism Group, Diabetes and Nutritional Sciences Division, School of Medicine, King's College London, London, UK.
authors.forename: Paul Anthony
authors.initials: PA
authors.lastname: Sharp
mesh_terms: D001205:Ascorbic Acid / Q000008:administration & dosage / Q000032:analysis / Q000378:metabolism; D015415:Biomarkers / Q000378:metabolism; D018938:Caco-2 Cells; D002664:Child Nutritional Physiological Phenomena; D002675:Child, Preschool; D004063:Digestion; D020895:Enterocytes / Q000378:metabolism*; D005293:Ferritins / Q000096:biosynthesis; D019648:Foods, Specialized / Q000032:analysis; D006358:Hot Temperature; D006801:Humans; D007223:Infant; D041943:Infant Formula / Q000737:chemistry*; D007227:Infant Nutritional Physiological Phenomena; D007408:Intestinal Absorption; D019266:Iron, Dietary / Q000008:administration & dosage / Q000032:analysis / Q000378:metabolism*; D009753:Nutritive Value; D009844:Oligosaccharides / Q000008:administration & dosage / Q000032:analysis / Q000378:metabolism; D056692:Prebiotics / Q000008:administration & dosage / Q000032:analysis*; D014312:Trisaccharides / Q000008:administration & dosage / Q000032:analysis / Q000378:metabolism
chemical_list: D015415:Biomarkers; D019266:Iron, Dietary; D009844:Oligosaccharides; D056692:Prebiotics; D014312:Trisaccharides; C116580:fructooligosaccharide; C072242:4'-galactooligosaccharide; D005293:Ferritins; D001205:Ascorbic Acid
keywords: Bioavailability; Caco-2; Iron; Prebiotics; Young Child Formulae; Young children