Randomised clinical trial: low-FODMAP rye bread vs. regular rye bread to relieve the symptoms of irritable bowel syndrome

Aliment Pharmacol Ther. 2016 Sep;44(5):460-70. doi: 10.1111/apt.13726. Epub 2016 Jul 15.


Background: Grains are high in FODMAPs (Fermentable Oligo-, Di-, Monosaccharides And Polyols) and often considered as triggers of IBS symptoms.

Aim: To evaluate if rye bread low in FODMAPs would be better tolerated than regular rye bread in subjects with IBS.

Methods: The study was conducted as a randomised double blind controlled cross-over study (n = 87). Participants were supplied with both regular rye bread and low-FODMAP rye bread for 4 weeks. Symptoms were measured with a symptom severity scoring system (IBS-SSS) and visual analogue scale (VAS) assessments of individual symptoms. Quality of life was monitored. Colonic fermentation was measured by the breath hydrogen test and dietary intake by food diaries.

Results: Dietary fibre intake increased during both study periods compared to baseline. Many signs of IBS i.e. flatulence, abdominal pain, cramps and stomach rumbling were milder on the low-FODMAP rye bread (P-values: 0.04; 0.049; 0.01 and 0.001). The mean of VAS measurements was favourable towards LF bread [-3 (95% CI): -6 to -1, P = 0.02] but no differences were detected in IBS-SSS or quality of life. The AUC of breath hydrogen values was significantly lower during the low-FODMAP bread period (median 52.9 vs. 72.6; P = 0.01).

Conclusions: Low-FODMAP rye bread helps IBS patients to control their symptoms and reduces gastrointestinal gas accumulation. However, replacing regular rye bread by low-FODMAP bread without concomitant broader dietary changes does not improve quality of life or IBS-SSS. Nonetheless, inclusion of low-FODMAP rye bread in diet might be one way that IBS patients could increase their fibre intake.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Abdominal Pain / diet therapy
  • Adult
  • Bread*
  • Breath Tests
  • Cross-Over Studies
  • Diet / methods*
  • Diet Records
  • Disaccharides / administration & dosage
  • Double-Blind Method
  • Female
  • Fermentation*
  • Humans
  • Irritable Bowel Syndrome / diagnosis*
  • Irritable Bowel Syndrome / diet therapy*
  • Male
  • Middle Aged
  • Monosaccharides / administration & dosage
  • Oligosaccharides / administration & dosage
  • Polymers / administration & dosage
  • Quality of Life
  • Secale*


  • Disaccharides
  • Monosaccharides
  • Oligosaccharides
  • Polymers
  • polyol