Western Dietary Pattern Is Associated with Irritable Bowel Syndrome in the French NutriNet Cohort

Background: Diet appears to play a key role in the pathogenesis of the irritable bowel syndrome (IBS). Some dietary patterns (DP) could increase the risk of triggering or worsening IBS symptoms. This cross-sectional study aimed to assess the association between a posteriori derived DP and IBS in a large French population, the web-based NutriNet-Santé cohort. Methods: Study population included participants of the NutriNet-Santé study who completed a questionnaire based on Rome III criteria assessing IBS. A principal component analysis (PCA) was performed to identify major DPs based on 29 food groups’ consumption. Associations between DP quintiles and IBS were investigated with multivariable logistic regressions. Results: 44,350 participants were included, with 2423 (5.5%) presenting IBS. Three major DP were extracted using PCA, “healthy,” “western,” and “traditional.” After adjustments on confounders, the “western” DP was positively associated with IBS (OR (Q5 vs. Q1) = 1.38, 95% CI 1.19–1.61, p trend < 0.0001) and the “traditional” DP was positively associated with IBS in women (OR (Q5 vs. Q1) = 1.29 95% CI 1.08–1.54, p trend = 0.001). Conclusions: In this study, a “western” DP—highly correlated with the consumption of fatty and sugary products and snacks—was associated with a moderate increased risk of IBS.