Inflammatory Potential of the Diet and Risk of Crohn's Disease and Ulcerative Colitis

Association between dietary factors and the risk of developing inflammatory bowel disease (IBD) has been studied extensively. However, identification of deleterious dietary patterns merits further study. To investigate the risk of developing Crohn's disease (CD) and ulcerative colitis (UC) according to the inflammatory score of the diet (ISD) in the multinational European Prospective Investigation into Cancer and Nutrition (EPIC) cohort. We used validated food frequency questionnaires collected at baseline to compute ISD scores. We estimated the association between ISD score and risks of CD and UC risks using Cox models stratified by centre, sex and age. We adjusted for smoking status, BMI, physical activity, energy intake, educational level and alcohol intake. We included 394,255 individuals including 184 incident cases of CD and 459 of UC after median follow-up of 13.6 years (4,889,910 person-years). High ISD scores were associated with a higher risk of CD (fourth vs. first quartile-adjusted HR: 1.88, 95% CI: 1.14-3.10; p-trend < 0.01) but not of UC (adjusted HR: 0.85, 95% CI: 0.63-1.15; p-trend 0.21). For CD, this association was mainly observed for women (adjusted HR: 2.14, 95% CI: 1.17-3.91; p-trend < 0.01). On subgroup analyses, those differences were mainly driven by low intakes of fibre, mono-unsaturated fatty acids, vitamin C, magnesium, onion and alcohol. A high ISD score is associated with a higher risk of developing CD but not UC. These results should be taken into account in high-risk populations.