Empirically derived food-based inflammatory potential of the diet, irritable bowel syndrome, and its severity.

Abstract

To our knowledge, no studies have examined the association between the empirically derived food-based dietary inflammatory index (FDII) and irritable bowel syndrome (IBS). The aim of this study was to examine the relationship between the FDII score and IBS in a large sample of Iranian adults. In this cross-sectional study, the dietary intakes of 3363 adults were assessed using a validated dish-based 106-item semi-quantitative food frequency questionnaire (DS-FFQ). The FDII was calculated based on the dietary intakes of food groups derived from DS-FFQ. IBS was assessed using a modified Persian version of the Rome III questionnaire. Participants in the top quintile of the FDII score had a 42% greater risk for IBS than those in the bottom quintile (odds ratio [OR], 1.42; 95% confidence interval [CI], 1.08-1.88). Among women, we observed a significant direct association between the FDII score and IBS after adjustment for potential confounders (OR, 1.44; 95% CI, 1.01-2.04). By body mass index (BMI) status, normal weight subjects (BMI <25 kg/m2) in the top quintile of the FDII score had higher risk for IBS (OR, 1.60; 95% CI, 1.07-2.35) than those in the bottom quintile. These associations were not observed in men or in participants with a BMI ≥25 kg/m2. There was no significant association between the FDII score and IBS subtypes. No significant association between the FDII score and IBS severity was observed. Consumption of a pro-inflammatory diet was associated with increased risk for IBS, especially in women and in individuals with a BMI <25 kg/m2.