Diet in subjects with irritable bowel syndrome: A cross-sectional study in the general population

BACKGROUND Patients with irritable bowel syndrome (IBS) often relate symptoms to the intake of certain foods. This study assesses differences in diet in subjects with and without IBS. METHODS The cross-sectional, population-based study was conducted in Norway in 2001. Out of 11078 invited subjects, 4621 completed a survey about abdominal complaints and intake of common food items. IBS and IBS subgroups were classified according to Rome II criteria. RESULTS IBS was diagnosed in 388 subjects (8.4%) and, of these, 26.5% had constipation-predominant IBS (C-IBS), 44.8% alternating IBS (A-IBS), and 28.6% diarrhoea-predominant IBS (D-IBS). Low intake of dairy products (portions/day) (Odds Ratio 0.85 [CI 0.78 to 0.93], p = 0.001) and high intake of water (100 ml/day) (1.08 [1.02 to 1.15], p = 0.002), tea (1.05 [1.01 to 1.10], p = 0.019) and carbonated beverages (1.07 [1.01 to 1.14], p = 0.023) were associated with IBS. A lower intake of dairy products and a higher intake of alcohol and carbonated beverages were associated with D-IBS and a higher intake of water and tea was associated with A-IBS. In subjects with IBS the severity of symptoms was associated with a higher intake of vegetables and potatoes in subjects with C-IBS, with a higher intake of vegetables in subjects with A-IBS, and with a higher intake of fruits and berries, carbonated beverages and alcohol in subjects with D-IBS. CONCLUSIONS In this study, the diet differed in subjects with and without IBS and between IBS subgroups and was associated with the severity of symptoms.