Dietary risk factors for inflammatory bowel disease in Shanghai: A case-control study

Background and Objectives: Inflammatory bowel disease (IBD) is a multifactorial condition involving the complex interplay of genomics, microbiota, immunology, environment, and personal behaviors, particularly diet. Methods and Study Design: A case-control study in a tertiary referral hospital. Fifty patients with IBD and 50 controls without gastrointestinal diseases were enrolled consecutively from October 1, 2016, to December 31, 2017. Sociodemographic and Food Frequency Questionnaires (FFQs) were completed, and dietary risk factors for IBD were identified. Results: Six major foods were associated with the recurrent incidence of IBD (p < 0.05): chili, fish, milk, nuts, eggs, and fruit. Logistic regression analysis revealed that eating chili and drinking milk more than three times weekly increased the risk of relapse, as did eating fish and nuts one or two times weekly. Eating fruit more than once weekly reduced the risk of IBD. Fish, seafood, vegetables, nuts, beef, and fruit, along with a history of food allergy, were associated with a high risk of clinically recurrent IBD. Dietary patterns featuring seafood and nuts also increased the risk of relapse. Conclusions: The consumption of chili, milk, fish, and nuts beyond moderate weekly frequencies increased the risk of IBD, whereas fruit consumption was consistently protective against IBD development. Relapse susceptibility was also associated with a history of food allergy. Thus, IBD risk management can involve more personalized and less restrictive dietary patterns, as well as the enforcement of weekly dose thresholds. Uncertainty remains regarding association differentials between ulcerative colitis (UC) and Crohn's disease (CD).