Use of the low-FODMAP diet in inflammatory bowel disease

Irritable bowel syndrome (IBS)-like symptoms are not uncommon in patients with quiescent inflammatory bowel disease (IBD). While gluten-free diet is applied by patients, there are no reported interventional studies. The low-FODMAP diet, on the other hand, has efficacy similar to that seen in patients with IBS in three unblinded or observational studies of IBD cohorts who had well-controlled inflammatory disease and in one small randomized cross-over study. FODMAP intake by patients with IBD is not elevated, and, in one study, fructan intakes were lower in patients with Crohn's disease than in controls. There is no clear relationship between the level of FODMAP intake and intestinal inflammation. The risk of compromising nutritional status with a restrictive diet must be seriously considered especially as under-nutrition is already common in this patient population. The effects of FODMAPs on the gut microbiota of patients with Crohn's disease mimic that in IBS, with a balance between prebiosis from the addition of FODMAPs and loss of prebiosis from their reduction. As undernutrition is common in IBD, the use of restrictive diets should be supervised by a dietitian. Thus, low-FODMAP diet is a viable option for IBS-like symptoms but should be carefully supervised to mitigate risk.