What is the role of gluten free diet in IBS?
Although many IBS patients empirically report an improvement in symptoms on a gluten-free diet, rigorous evidence from controlled trials is lacking. After a 4-week trial in 45 IBS-D patients of a gluten-containing or a gluten-free diet, patients on the gluten-containing diet had more bowel movements per day as compared with patients on the gluten-free diet (P = 0.04) as well as higher small bowel permeability. However, in a separate study, 37 IBS patients were placed on a low FODMAP diet and then randomized to either a high-gluten, low-gluten, or gluten-free diet. All patients reported significant improvement in symptoms on the low FODMAP diet, but after introduction of the high-gluten, low-gluten, or gluten-free diet, all patients reported worsening of symptoms to a similar degree regardless of diet.
However, a recent metaanalysis found the pooled prevalence of IBS symptoms in patients with celiac disease to be 38% (95% CI, 27%-50%) and only 5.6% in controls (95% CI, 3.23%-9.7%). As compared with controls, among celiac disease patients who were not adherent to a gluten-free diet, IBS-type symptoms were more prevalent versus adherent celiac disease patients.