“This is the only methodically rigorous clinical trial to show that diet-based therapy can not only improve symptoms, but also quality of life in patients with IBS,” said lead researcher Shanti Eswaran, an assistant clinical professor at the University of Michigan Health System who researches the role of diet and food in functional bowel diseases such as IBS.
The new study measured the degree of relief from low FODMAP, a frequently recommended diet, which stands for Fermentable Oligo-Di-Monosaccharides and Polyols. This diet excludes many compounds found in wheat, certain fruits and vegetables, garlic, onions, and sugar substitutes.
Over a six-week process, registered dietitians educated and monitored the progress of more than 90 IBS patients. Roughly half followed a prescribed low FODMAP diet, and half were a control group that used a common-sense regimen, cutting down on large meals, binges, and known irritants such as caffeine and alcohol.
The researchers found that more than 50% of the patients on the low FODMAP diet had major improvement of their abdominal pain, compared with 20% of the control group. There was also more improvement of other bothersome symptoms compared to the control group: bloating, diarrhea, and stool urgency. In addition, at four weeks, the proportion of patients with a meaningful improvement in IBS quality of life was significantly higher in the low FODMAP group compared to the control group—61% versus 27%.
However, the researchers noted that because of the many unknowns about the chemical causes and triggers of IBS, the list of “bad” foods is exhaustive and elusive, and help from a dietician is highly recommended. The next step is for the researchers to more precisely determine the underlying chemistry of how and why particular foods can yield dramatically different results for different people.
