Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder, which is a heterogeneous condition with multiple etiologies, including abnormal reactions related to foods.1,2 Indeed, many patients with IBS commonly report adverse reactions against certain foods.3,4 Moreover, many studies have investigated the role of food allergies in patients with IBS5–8; however, the underlying mechanisms related to certain foods have not been fully elucidated. In this issue of Gastroenterology, the study by Fritscher-Ravens et al9 provides evidence of abnormal reactions to individual foods and associated pathophysiologic changes in patients with IBS.