Low Fermentable Oligosaccharides, Disaccharides, Monosaccharides, And Polyols Diet Compared With Traditional Dietary Advice For Diarrhea-predominant Irritable Bowel Syndrome: A Parallel-group, Randomized Controlled Trial With Analysis Of Clinical And Microbiological Factors Associated With Patient Outcomes
|Values||After three weeks of low-FODMAP diet, fecal concentrations of n-butyric acid were lower (p=0.045) but i-butyric acid and i-valeric acid concentrations were elevated (p=0.011 and p=0.009).|
|Trial Design||Randomized trial|
|Trial Length||2-4 Weeks|
|Number of Subjects||108|
|Age Range||30-44, 45-64|
|Body Types||Overweight, Average|
In this randomized, parallel-group controlled trial, 108 patients with IBS-D were assigned to a 3-week low-FODMAP diet or traditional dietary advice based on modified National Institute for Clinical Excellence guidelines. Fecal samples were collected before and after the intervention for the analysis of short chain fatty acids and fecal microbiota. The primary endpoint was a ≥50 point reduction in the IBS Severity Scoring System.
Intention-to-treat analysis indicated the primary endpoint was met in 55.6% of the patients in the low-FODMAP group and 48.1% in the traditional dietary advice group. During the first week, patients in the low-FODMAP group experienced greater reductions in defecation and excessive flatulence compared to the traditional dietary advice group, but these differences were absent thereafter. After the first week, abdominal pain and urgency also improved in the low-FODMAP group, but stool consistency did not improve in this group. The traditional dietary advice group did experience improvements in abdominal pain, stool consistency, excessive flatulence, and urgency.
The low-FODMAP diet reduced carbohydrate-fermenting bacteria and associated saccharolytic fermentation activity. These changes were associated with symptom improvement in responders, and high baseline levels of saccharolytic activity were associated with greater symptom burden.
Alpha-diversity based on the Shannon index was higher after the low-FODMAP diet, and concentrations of certain short-chain fatty acids were both elevated and reduced.