title: Fecal Fermentation in Irritable Bowel Syndrome: Influence of Dietary Restriction of Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols.
abstract: OBJECTIVE
  Dietary restriction of fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAPs) may relieve symptoms in patients with irritable bowel syndrome (IBS). We investigated whether this diet alters microbial fermentation, a process that may be involved in IBS symptom generation.
  
  
  METHODS
  Patients with IBS were included consecutively to participate in a 4-week FODMAP restricted diet. IBS symptoms were evaluated by using the IBS severity scoring system (IBS-SSS). Short-chain fatty acids (SCFAs) were analyzed in fecal samples before and after the dietary intervention, both at baseline and after in vitro fermentation for 24 h.
  
  
  RESULTS
  Sixty-three patients completed the study. Following the dietary intervention, IBS-SSS scores improved significantly (p < 0.0001). Total SCFA levels were reduced in fecal samples analyzed both at baseline (p = 0.005) and after in vitro fermentation for 24 h (p = 0.013). Following diet, baseline levels of acetic (p = 0.003) and n-butyric acids (p = 0.009) decreased, whereas 24 h levels of i-butyric (p = 0.003) and i-valeric acids (p = 0.003) increased. Fecal SCFA levels and IBS symptom scores were not correlated.
  
  
  CONCLUSIONS
  Dietary FODMAP restriction markedly modulated fecal fermentation in patients with IBS. Saccharolytic fermentation decreased, while proteolytic fermentation increased, apparently independent of symptoms.
authors.affiliation: Unger-Vetlesen Institute, Lovisenberg Diaconal Hospital, Oslo, Norway.
authors.forename: Jørgen
authors.initials: J
authors.lastname: Valeur
authors.forename: Arne Gustav
authors.initials: AG
authors.lastname: Røseth
authors.forename: Torunn
authors.initials: T
authors.lastname: Knudsen
authors.forename: Gunn Helen
authors.initials: GH
authors.lastname: Malmstrøm
authors.forename: Jennifer T
authors.initials: JT
authors.lastname: Fiennes
authors.forename: Tore
authors.initials: T
authors.lastname: Midtvedt
authors.forename: Arnold
authors.initials: A
authors.lastname: Berstad
mesh_terms: D000328:Adult; D000368:Aged; D001944:Breath Tests; D003113:Colonoscopy; D050528:Diet, Carbohydrate-Restricted; D004187:Disaccharides / Q000378:metabolism; D005232:Fatty Acids, Volatile / Q000032:analysis* / Q000378:metabolism; D005243:Feces / Q000737:chemistry*; D005260:Female; D005285:Fermentation; D000069196:Gastrointestinal Microbiome; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000178:diet therapy* / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D009005:Monosaccharides / Q000378:metabolism; D009664:Norway; D009844:Oligosaccharides / Q000378:metabolism; D011108:Polymers / Q000378:metabolism; D012720:Severity of Illness Index; D055815:Young Adult
chemical_list: D004187:Disaccharides; D005232:Fatty Acids, Volatile; D009005:Monosaccharides; D009844:Oligosaccharides; D011108:Polymers; C024617:polyol