Habitual dietary fibre intake influences gut microbiota response to an inulin-type fructan prebiotic: a randomised, double-blind, placebo-controlled, cross-over, human intervention study

Br J Nutr. 2018 Jan;119(2):176-189. doi: 10.1017/S0007114517003440. Epub 2018 Jan 8.


Dysbiotic gut microbiota have been implicated in human disease. Diet-based therapeutic strategies have been used to manipulate the gut microbiota towards a more favourable profile. However, it has been demonstrated that large inter-individual variability exists in gut microbiota response to a dietary intervention. The primary objective of this study was to investigate whether habitually low dietary fibre (LDF) v. high dietary fibre (HDF) intakes influence gut microbiota response to an inulin-type fructan prebiotic. In this randomised, double-blind, placebo-controlled, cross-over study, thirty-four healthy participants were classified as LDF or HDF consumers. Gut microbiota composition (16S rRNA bacterial gene sequencing) and SCFA concentrations were assessed following 3 weeks of daily prebiotic supplementation (Orafti® Synergy 1; 16 g/d) or placebo (Glucidex® 29 Premium; 16 g/d), as well as after 3 weeks of the alternative intervention, following a 3-week washout period. In the LDF group, the prebiotic intervention led to an increase in Bifidobacterium (P=0·001). In the HDF group, the prebiotic intervention led to an increase in Bifidobacterium (P<0·001) and Faecalibacterium (P=0·010) and decreases in Coprococcus (P=0·010), Dorea (P=0·043) and Ruminococcus (Lachnospiraceae family) (P=0·032). This study demonstrates that those with HDF intakes have a greater gut microbiota response and are therefore more likely to benefit from an inulin-type fructan prebiotic than those with LDF intakes. Future studies aiming to modulate the gut microbiota and improve host health, using an inulin-type fructan prebiotic, should take habitual dietary fibre intake into account.

Keywords: HDF high dietary fibre; LDF low dietary fibre; 16S rRNA gene sequencing; Gut microbiota; Habitual dietary fibres; Inulin-type fructan prebiotics; Responsiveness.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Bacteria / classification
  • Bacteria / genetics
  • Bacteria / isolation & purification
  • Bifidobacterium / growth & development
  • Cross-Over Studies
  • Dietary Fiber / administration & dosage
  • Double-Blind Method
  • Fatty Acids, Volatile / analysis
  • Feces / chemistry
  • Feces / microbiology
  • Female
  • Gastrointestinal Microbiome / drug effects
  • Gastrointestinal Microbiome / genetics
  • Gastrointestinal Microbiome / physiology*
  • Humans
  • Inulin / administration & dosage*
  • Male
  • Middle Aged
  • New Zealand
  • Placebos
  • Prebiotics / administration & dosage*
  • Prebiotics / adverse effects
  • RNA, Ribosomal, 16S / analysis


  • Dietary Fiber
  • Fatty Acids, Volatile
  • Placebos
  • Prebiotics
  • RNA, Ribosomal, 16S
  • Inulin

Associated data

  • ANZCTR/ACTRN12615000922572