Irritable bowel syndrome (IBS) is among the most prevalent gastrointestinal (GI) conditions.Since the pathophysiology of this syndrome is still unclear. It has been shown that low FODMAP (fermentable oligosaccharide, disaccharide, monosaccharide, and polyol) diet improves IBS symptoms by up to 70%.One of the most consumed food items in the FODMAPs is wheat, which is one of the most prevalent triggers of IBS; however, it is not yet elucidated which of wheat constituents ( FODMAPs or gluten) contribute to the IBS symptoms.The aim of this research was to show the gluten-related argument and determine if gluten can trigger symptoms in IBS patients.

Participants were randomly assigned to one of two groups: the control group received a low FODMAP diet with 5 gram/day rice flour, and the intervention group received 5 gram/day gluten powder. The duration of diet was 6 weeks and subjects completed three days of dietary recalls at the end of week 2 and week 6 to assess their adherence to low FODMAP diet.

From 63 patients referred to our clinics, 49 patients enrolled in the study.Significant improvements were observed in in both gluten and placebo groups but in placebo group more than intervention groups(P< 0.05).The symptoms worsened only in five participants in gluten group . There were no significant difference between two groups’ symptoms before and after adjustment for baseline value. dietary FODMAPs were less than two gram/day in both groups at 2nd and 6th weeks of intervention without any significant difference between two groups.

This study has demonstrated that gluten containing diet did not have any adverse effect on the clinical symptoms and QOL in most of IBS patients. It seems that the wheat and barley exaggerate the IBS symptoms mainly through their fructan content, while their gluten is responsible for symptoms only in few percent of patients