Fig. 1

Pathogenesis of ulcerative colitis (UC) and the impact of diet. Under normal conditions, symbiotic interactions between the microbiome, intestinal epithelium, and immune system are crucial for maintaining intestinal homeostasis. However, any disturbance in this balance can lead to dysbiosis, immune dysregulation, and inflammation, all of which contribute to impairments in the intestinal barrier. The ensuing barrier dysfunction further amplifies the cycle of pathogenic mechanisms at the heart of UC. As the disease progresses, these pathogenic factors intensify, leading to an escalation in symptoms (left). Diet emerges as a critical factor among various risk elements, impacting epithelial barrier integrity and stability through both direct and indirect pathways. It influences the entire trajectory of UC management, from pre-clinical prevention through to remission maintenance and treatment during active phases. This review provides current insights into the role of dietary content and eating behaviors in UC, detailing the effects of specific foods and food groups, nutrients, and the practice of intermittent fasting (right). AID = the Anti-Inflammatory Diet; SCD = the Specific Carbohydrate Diet; MED = the Mediterranean diet; LFD = the low-FODMAP diet