Inulin-type fructans and whey protein both modulate appetite but only fructans alter gut microbiota in adults with overweight/obesity: A randomized controlled trial

Mol Nutr Food Res. 2017 Nov;61(11). doi: 10.1002/mnfr.201700484. Epub 2017 Aug 29.


Scope: Independently, prebiotics and dietary protein have been shown to improve weight loss and/or alter appetite. Our objective was to determine the effect of combined prebiotic and whey protein on appetite, body composition and gut microbiota in adults with overweight/obesity.

Methods and results: In a 12 week, placebo-controlled, double-blind study, 125 adults with overweight/obesity were randomly assigned to receive isocaloric snack bars of: (1) Control; (2) Inulin-type fructans (ITF); (3) Whey protein; (4) ITF + Whey protein. Appetite, body composition and gut microbiota composition/genetic potential were assessed. Compared to Control, body fat was significantly reduced in the Whey protein group at 12 wks. Hunger, desire to eat and prospective food consumption were all lower with ITF, Whey protein and ITF + Whey protein compared to Control at 12 wks. Microbial community structure differed from 0 to 12 wks in the ITF and ITF +Whey Protein groups (i.e. increased Bifidobacterium) but not Whey Protein or Control. Changes in microbial genetic potential were seen between Control and ITF-containing treatments.

Conclusion: Adding ITF, whey protein or both to snack bars improved several aspects of appetite control. Changes in gut microbiota may explain in part the effects of ITF but likely not whey protein.

Keywords: Appetite; Dairy protein; Gut microbiota; Inulin/oligofructose; Weight management.

Publication types

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

MeSH terms

  • Adiposity
  • Adult
  • Appetite Depressants / adverse effects
  • Appetite Depressants / therapeutic use*
  • Bifidobacterium / classification
  • Bifidobacterium / growth & development
  • Bifidobacterium / isolation & purification
  • Body Mass Index
  • Dietary Carbohydrates / adverse effects
  • Dietary Carbohydrates / therapeutic use*
  • Dietary Supplements* / adverse effects
  • Double-Blind Method
  • Dysbiosis / diet therapy*
  • Dysbiosis / microbiology
  • Energy Intake
  • Feces / microbiology
  • Female
  • Fructans / adverse effects
  • Fructans / therapeutic use*
  • Gastrointestinal Microbiome
  • Humans
  • Lost to Follow-Up
  • Male
  • Middle Aged
  • Molecular Typing
  • Obesity / diet therapy
  • Obesity / microbiology
  • Overweight / diet therapy*
  • Overweight / microbiology
  • Patient Dropouts
  • Prebiotics
  • Principal Component Analysis
  • Whey Proteins / adverse effects
  • Whey Proteins / therapeutic use*


  • Appetite Depressants
  • Dietary Carbohydrates
  • Fructans
  • Prebiotics
  • Whey Proteins