Gluten-Free Diet Seems to Reduce Symptoms and Improve Gut Health in Irritable Bowel Syndrome

Celiac.com 01/02/2023 - There's been a good bit of research to show that a gluten-free diet can reduce symptoms in some patients with irritable bowel syndrome (IBS), but there are currently no good answers for why that might be.

To get a better idea for the reasons, a team of researchers recently set out to compare the effects of a gluten-free and gluten-containing diet on IBS symptoms and the gut microenvironment, and to identify predictors of response to the gluten-free diet in IBS. Here's what they found.

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The research team included Joost P. Algera; Maria K. Magnusson; Lena Öhman; Stine Störsrud; Magnus Simrén; and Hans Törnblom. They are variously affiliated with theDepartment of Molecular and Clinical Medicine, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden; the Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden; and the Center for Functional Gastrointestinal and Motility Disorders, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA.

Randomized Controlled Trial

For their randomized controlled trial, the team followed twenty patients with IBS, along with 18 healthy control subjects, all of whom followed a gluten-free diet during two 14-day intervention periods, during which they received meals sprinkled with either gluten, totaling 14 grams a day, or rice flour powder. Main outcomes included effects of the interventions on IBS symptoms and bowel habits. Secondary outcomes included effects of gluten-free diet on fecal microbiota and metabolite profile.

IBS symptoms improve on gluten-free diet

IBS symptoms improved during the gluten-free diet period, but not the gluten-containing period, with no difference between the interventions. 

Among other things, IBS patients on a gluten-free diet reported fewer loose stools. Meanwhile, patients with IBS and healthy control subjects showed specific metabolite profiles related to the gluten-free diet. True responders showed a reduction of IBS symptoms of 50 or greater solely after gluten-free period. 

The team distinguished non-responders based on microbiota and metabolite profiles resulting from the gluten-free diet. Based on the patient's metabolite profile before the intervention, the team was able to predict patient response to a gluten-free diet.

Gluten-free diet seems to improve gut health

From their findings, the team concludes that a gluten-free diet seems to improve the gut biome, and may help to reduce symptoms in some patients with IBS, especially with respect to bowel habits. 

Patient metabolite profiles can predict responsiveness to the gluten-free diet.

This study is important for people with IBS, as it provides some good data for the benefits of a gluten-free diet in many cases.

Read more in Aliment Pharmacol Ther. 2022;56(9):1318-1327