Effect of fructose-reduced diet in patients with irritable bowel syndrome, and its correlation to a standard fructose breath test

Scand J Gastroenterol. 2013 Aug;48(8):936-43. doi: 10.3109/00365521.2013.812139. Epub 2013 Jul 8.


Objectives: To perform a validation of dairy registrations for use as diagnostic tool in IBS and fructose malabsorption (FM). To investigate the precision of the fructose breath test (FBT) as compared with symptom score reduction on fructose-reduced diet (FRD) in a cohort of patients with Rome II defined irritable bowel syndrome (IBS).

Design: IBS patients diagnosed according to the Rome II criteria and with no organic gastrointestinal disease were enrolled. The patients were randomized in an open study design with a 2 week run-in on IBS diet, followed by 4 weeks w/wo additional FRD. FBT was performed in all patients. Dairy registrations of stool frequency and consistency as well as abdominal pain/discomfort and bloating on a visual analog scale (VAS) were performed during the whole study.

Results: A total of 182 subjects performed the study according to protocol (88 FRD, 94 controls). The VAS symptom registration performed well in validation procedures, whereas stool data showed less impressive characteristics. FRD improved symptom scores (abdominal pain/discomfort and bloating) significantly whereas no changes were observed in the control group. The effect of FRD on the stool frequency was modest but no effect was observed on the stool consistency. The FBT did not discriminate between patients with and without effect of FRD, and even in the group with a negative FBT significant improvement of symptom scores was observed.

Conclusion: VAS measures yield reliable symptom evaluation in dairy registrations of IBS. FRD improves symptom scores in IBS patients independent of results from the FBT.

Publication types

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

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Biomarkers / metabolism
  • Breath Tests
  • Dietary Carbohydrates / adverse effects*
  • Female
  • Fructose / adverse effects*
  • Humans
  • Hydrogen / metabolism*
  • Irritable Bowel Syndrome / diagnosis
  • Irritable Bowel Syndrome / diet therapy*
  • Irritable Bowel Syndrome / etiology
  • Irritable Bowel Syndrome / metabolism
  • Malabsorption Syndromes / complications
  • Malabsorption Syndromes / diagnosis*
  • Malabsorption Syndromes / diet therapy
  • Malabsorption Syndromes / metabolism
  • Male
  • Medical Records
  • Methane / metabolism*
  • Middle Aged
  • Prospective Studies
  • Reproducibility of Results
  • Treatment Outcome
  • Visual Analog Scale
  • Young Adult


  • Biomarkers
  • Dietary Carbohydrates
  • Fructose
  • Hydrogen
  • Methane