title: Effects of iron supplementation on dominant bacterial groups in the gut, faecal SCFA and gut inflammation: a randomised, placebo-controlled intervention trial in South African children.
abstract: Fe supplementation is a common strategy to correct Fe-deficiency anaemia in children; however, it may modify the gut microbiota and increase the risk for enteropathogenic infection. In the present study, we studied the impact of Fe supplementation on the abundance of dominant bacterial groups in the gut, faecal SCFA concentration and gut inflammation in children living in rural South Africa. In a randomised, placebo-controlled intervention trial of 38 weeks, 6- to 11-year-old children with Fe deficiency received orally either tablets containing 50 mg Fe as FeSO₄ (n 22) for 4 d/week or identical placebo (n 27). In addition, Fe-sufficient children (n 24) were included as a non-treated reference group. Faecal samples were analysed at baseline and at 2, 12 and 38 weeks to determine the effects of Fe supplementation on ten bacterial groups in the gut (quantitative PCR), faecal SCFA concentration (HPLC) and gut inflammation (faecal calprotectin concentration). At baseline, concentrations of bacterial groups in the gut, faecal SCFA and faecal calprotectin did not differ between Fe-deficient and Fe-sufficient children. Fe supplementation significantly improved Fe status in Fe-deficient children and did not significantly increase faecal calprotectin concentration. Moreover, no significant effect of Fe treatment or time × treatment interaction on the concentrations of bacterial groups in the gut or faecal SCFA was observed compared with the placebo treatment. Also, there were no significant differences observed in the concentrations of any of the bacterial target groups or faecal SCFA at 2, 12 or 38 weeks between the three groups of children when correcting for baseline values. The present study suggests that in African children with a low enteropathogen burden, Fe status and dietary Fe supplementation did not significantly affect the dominant bacterial groups in the gut, faecal SCFA concentration or gut inflammation.
authors.affiliation: Laboratory of Food Biotechnology, Institute of Food, Nutrition and Health,ETH Zurich, Schmelzbergstrasse 7,8092Zurich,Switzerland.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Dostal
authors.affiliation: Laboratory of Human Nutrition, Institute of Food, Nutrition and Health,ETH Zurich, Schmelzbergstrasse 7,8092Zurich,Switzerland.
authors.forename: Jeannine
authors.initials: J
authors.lastname: Baumgartner
authors.affiliation: Laboratory of Food Biotechnology, Institute of Food, Nutrition and Health,ETH Zurich, Schmelzbergstrasse 7,8092Zurich,Switzerland.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Riesen
authors.affiliation: Laboratory of Food Biotechnology, Institute of Food, Nutrition and Health,ETH Zurich, Schmelzbergstrasse 7,8092Zurich,Switzerland.
authors.forename: Christophe
authors.initials: C
authors.lastname: Chassard
authors.affiliation: Centre of Excellence for Nutrition, North-West University,Potchefstroom Campus,South Africa.
authors.forename: Cornelius M
authors.initials: CM
authors.lastname: Smuts
authors.affiliation: Laboratory of Human Nutrition, Institute of Food, Nutrition and Health,ETH Zurich, Schmelzbergstrasse 7,8092Zurich,Switzerland.
authors.forename: Michael B
authors.initials: MB
authors.lastname: Zimmermann
authors.affiliation: Laboratory of Food Biotechnology, Institute of Food, Nutrition and Health,ETH Zurich, Schmelzbergstrasse 7,8092Zurich,Switzerland.
authors.forename: Christophe
authors.initials: C
authors.lastname: Lacroix
mesh_terms: D018798:Anemia, Iron-Deficiency / Q000178:diet therapy / Q000453:epidemiology / Q000276:immunology / Q000382:microbiology; D002648:Child; D019587:Dietary Supplements / Q000009:adverse effects*; D005232:Fatty Acids, Volatile / Q000032:analysis / Q000378:metabolism; D005243:Feces / Q000737:chemistry; D005260:Female; D005296:Ferrous Compounds / Q000008:administration & dosage; D005759:Gastroenteritis / Q000139:chemically induced / Q000453:epidemiology / Q000276:immunology / Q000382:microbiology; D005765:Gastrointestinal Agents / Q000009:adverse effects / Q000627:therapeutic use; D006090:Gram-Negative Bacteria / Q000254:growth & development* / Q000302:isolation & purification / Q000378:metabolism; D006094:Gram-Positive Bacteria / Q000254:growth & development* / Q000302:isolation & purification / Q000378:metabolism; D006397:Hematinics / Q000009:adverse effects* / Q000627:therapeutic use; D006801:Humans; D015994:Incidence; D007413:Intestinal Mucosa / Q000276:immunology / Q000378:metabolism / Q000382:microbiology*; D019266:Iron, Dietary / Q000009:adverse effects* / Q000627:therapeutic use; D039841:Leukocyte L1 Antigen Complex / Q000737:chemistry / Q000378:metabolism; D041741:Lower Gastrointestinal Tract / Q000276:immunology / Q000378:metabolism / Q000382:microbiology*; D008297:Male; D050296:Microbial Viability; D012423:Rural Health; D013019:South Africa / Q000453:epidemiology
chemical_list: D005232:Fatty Acids, Volatile; D005296:Ferrous Compounds; D005765:Gastrointestinal Agents; D006397:Hematinics; D019266:Iron, Dietary; D039841:Leukocyte L1 Antigen Complex; C020748:ferrous sulfate