Low-FODMAP Diet and Intestinal Permeability in Patients With Irritable Bowel Syndrome

Overview

This study aimed to evaluate the effects of a Low-FODMAP diet on intestinal permeability, symptom severity, and quality of life in patients with Irritable Bowel Syndrome (IBS). Twenty-four patients diagnosed with IBS according to the Rome IV criteria were randomized to either a Low-FODMAP diet or a traditional diet for four weeks. Stool zonulin family peptides (ZFP), IBS Symptom Severity Score (IBS-SSS), and IBS Quality of Life (IBS-QOL) questionnaires were recorded at baseline and after the dietary intervention. In the Low-FODMAP group, FODMAP-containing foods were gradually reintroduced under dietitian supervision, and assessments were repeated at week 16 to evaluate long-term effects.

Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder characterized by recurrent abdominal pain and altered bowel habits without an identifiable organic cause. Dietary factors and increased intestinal permeability have been proposed as potential mechanisms contributing to symptom development. The Low-FODMAP diet has been shown to improve IBS symptoms by reducing fermentable carbohydrate intake. However, its effects on intestinal barrier integrity remain unclear. This prospective randomized single-blind study was conducted at Istanbul Medipol Mega University Hospital between December 2023 and December 2024. Patients aged 18-65 years diagnosed with IBS according to the Rome IV criteria were included. Participants were randomized to follow either a Low-FODMAP diet or a traditional diet for four weeks. Stool zonulin family peptides (ZFP) were measured as a biomarker of intestinal permeability. Symptom severity and quality of life were evaluated using validated IBS-SSS and IBS-QOL questionnaires. After four weeks, patients in the Low-FODMAP group began a structured reintroduction phase where restricted foods were gradually reintroduced over twelve weeks. Follow-up assessments were performed at week 16 to evaluate long-term outcomes. The study investigated whether dietary FODMAP restriction could improve intestinal barrier function in addition to reducing symptom severity and improving quality of life in patients with IBS.