Patients with irritable bowel syndrome (IBS) exhibit low-grade inflammation and increased gut permeability. Dietary sugar has been shown to contribute to low-grade inflammation and increased gut permeability, and to correlate with gastrointestinal (GI) symptoms. The aim of the present study was to examine the effect of a starch- and sucrose-reduced diet (SSRD) on gastrointestinal (GI) and extra-intestinal symptoms in IBS. One hundred and five IBS patients (82 women, 46.06 ± 13.11 years), with irritable bowel syndrome-symptom severity scale (IBS-SSS) > 175, were randomized to SSRD for 4 weeks or continued ordinary eating habits. The visual analog scale for irritable bowel syndrome (VAS-IBS), IBS-SSS, and 4-day food diaries were collected at baseline and after 2 and 4 weeks. After the intervention, one-third of the patients did not fulfill the criteria for IBS/functional gastrointestinal disorder. Half of the participants changed from moderate/severe disease to no/mild disease according to IBS-SSS. Comparisons between the groups showed decreased weight and sweet cravings, and parallel decreases in total IBS-SSS and extra-intestinal IBS-SSS scores, in the intervention group compared to controls (p < 0.001 for all). When calculating separate extra-intestinal symptoms, belching (p = 0.001), muscle/joint pain (p = 0.029), urinary urgency (p = 0.017), and tiredness (p = 0.011) were decreased after introduction of SSRD compared to controls. In conclusion, SSRD improves both GI and extra-intestinal symptoms in IBS.
Keywords: diet; extra-intestinal symptoms; gastrointestinal symptoms; irritable bowel syndrome; starch; sucrose.