title: Assessment of complementary feeding of Canadian infants: effects on microbiome & oxidative stress, a randomized controlled trial.
abstract: The World Health Organization recommends exclusive breastfeeding until 6 months followed by introduction of iron-rich complementary foods (CFs). The aim of this study was to determine the impact of different iron-rich CFs on infant gut inflammation and microbiota.
  
  
  
  Eighty-seven exclusively breastfed infants were randomly assigned to receive one of the following as their first CF: iron-fortified cereal (Cer), iron-fortified cereal with fruit (Cer + Fr), or meat (M). Urine and stool samples were collected to assess reactive oxygen species (ROS) generation, gut microbiota and inflammation.
  
  
  
  Fecal iron differed across feeding groups (p < 0.001); levels were highest in the Cer group and lowest in M group. A significant increase of fecal ROS formation (p < 0.002) after the introduction of CFs was observed, but did not differ across feeding groups. Fecal calprotectin increased within all groups after the introduction of CFs (p = 0.004). Gut microbiota richness increased after introduction of M or Cer + Fr. Regardless of feeding group, Coriobacteriaceae were positively correlated with ROS and Staphylococcaceae were negatively correlated with calprotectin.
  
  
  
  Choice of first CF may influence gut inflammation and microbiota, potentially due to variations in iron absorption from different foods. Further research is warranted to fully characterize these associations and to establish implications for infant health. This study was registered in the ClinicalTrial.gov registry (Identifier No. NCT01790542 ).
  
  
  
  This study was registered in the ClinicalTrial.gov registry under the name "Assessment of Complementary Feeding of Canadian Infants" (Identifier No. NCT01790542 ) February 6, 2013.
authors.affiliation: Departement of Human Nutritional Sciences, University of Manitoba, Winnipeg, MB, Canada. qasemw@myumanitoba.ca.|Richardson Centre for Functional Foods and Nutraceuticals, 196 Innovation drive, University of Manitoba, Winnipeg, MB, Canada, R3T 6C5. qasemw@myumanitoba.ca.
authors.forename: Wafaa
authors.identifier: 0000-0002-4555-5371
authors.initials: W
authors.lastname: Qasem
authors.affiliation: Department of Pediatrics & Child Health, University of Manitoba, Winnipeg, MB, Canada.|Children's Hospital Research Institute of Manitoba, Winnipeg, MB, Canada.
authors.forename: Meghan B
authors.initials: MB
authors.lastname: Azad
authors.affiliation: Departement of Human Nutritional Sciences, University of Manitoba, Winnipeg, MB, Canada.|Richardson Centre for Functional Foods and Nutraceuticals, 196 Innovation drive, University of Manitoba, Winnipeg, MB, Canada, R3T 6C5.
authors.forename: Zakir
authors.initials: Z
authors.lastname: Hossain
authors.affiliation: Department of Animal Science, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Elnaz
authors.initials: E
authors.lastname: Azad
authors.affiliation: Richardson Centre for Functional Foods and Nutraceuticals, 196 Innovation drive, University of Manitoba, Winnipeg, MB, Canada, R3T 6C5.
authors.forename: Sarah
authors.initials: S
authors.lastname: Jorgensen
authors.affiliation: Departement of Human Nutritional Sciences, University of Manitoba, Winnipeg, MB, Canada.|Richardson Centre for Functional Foods and Nutraceuticals, 196 Innovation drive, University of Manitoba, Winnipeg, MB, Canada, R3T 6C5.
authors.forename: Sandra
authors.initials: S
authors.lastname: Castillo San Juan
authors.affiliation: Departement of Human Nutritional Sciences, University of Manitoba, Winnipeg, MB, Canada.|Richardson Centre for Functional Foods and Nutraceuticals, 196 Innovation drive, University of Manitoba, Winnipeg, MB, Canada, R3T 6C5.
authors.forename: Chenxi
authors.initials: C
authors.lastname: Cai
authors.affiliation: Children's Hospital Research Institute of Manitoba, Winnipeg, MB, Canada.|Department of Animal Science, University of Manitoba, Winnipeg, MB, Canada.|Department of Medical Microbiology, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Ehsan
authors.initials: E
authors.lastname: Khafipour
authors.affiliation: Department of Food Science, University of Manitoba, Winnipeg, MB, Canada.
authors.forename: Trust
authors.initials: T
authors.lastname: Beta
authors.affiliation: Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN, USA.
authors.forename: L Jackson
authors.initials: LJ
authors.lastname: Roberts
authors.affiliation: Departement of Human Nutritional Sciences, University of Manitoba, Winnipeg, MB, Canada.|Richardson Centre for Functional Foods and Nutraceuticals, 196 Innovation drive, University of Manitoba, Winnipeg, MB, Canada, R3T 6C5.|Children's Hospital Research Institute of Manitoba, Winnipeg, MB, Canada.
authors.forename: James
authors.initials: J
authors.lastname: Friel
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D002170:Canada; D002523:Edible Grain; D005243:Feces / Q000737:chemistry / Q000382:microbiology; D005260:Female; D005527:Food, Fortified; D005638:Fruit; D006801:Humans; D007223:Infant; D007224:Infant Care / Q000379:methods*; D007225:Infant Food; D007227:Infant Nutritional Physiological Phenomena / Q000502:physiology*; D007501:Iron; D008297:Male; D008460:Meat; D064307:Microbiota; D017063:Outcome Assessment, Health Care; D018384:Oxidative Stress; D017382:Reactive Oxygen Species / Q000378:metabolism; D016037:Single-Blind Method
chemical_list: D015415:Biomarkers; D017382:Reactive Oxygen Species; D007501:Iron
keywords: Breastfed infants; Complementary feeding; Iron fortified cereal; Meat; Microbiome