Dietary Interventions and Oral Nutritional Supplementation in Inflammatory Bowel Disease: Current Evidence and Future Directions

Background/Objectives: Inflammatory Bowel Diseases (IBD), including Crohn's Disease (CD) and Ulcerative Colitis (UC), are chronic disorders with complex pathophysiology involving immune dysregulation, gut microbiota alterations, and environmental triggers. Diet plays a critical role in disease onset and management. This review examines current evidence on dietary interventions and oral nutritional supplementation (ONS) in IBD management, assessing impacts on disease activity and clinical outcomes. Methods: A comprehensive literature search was conducted using PubMed, Scopus, and Web of Science databases, analyzing studies on various dietary approaches and ONS in IBD. Results: Exclusive Enteral Nutrition (EEN) remains firmly established as first-line therapy for pediatric CD, achieving remission rates comparable to corticosteroids while promoting mucosal healing and avoiding steroid-related adverse effects. The Crohn's Disease Exclusion Diet with Partial Enteral Nutrition demonstrates efficacy comparable to EEN with superior long-term adherence. The Mediterranean Diet represents a sustainable anti-inflammatory approach particularly suited for maintenance therapy. Emerging evidence supports other targeted interventions including low-FODMAP diet for functional symptoms and low-emulsifier diets for active CD. ONS effectively addresses malnutrition in IBD, with formulations ranging from elemental to specialized immunomodulating products tailored to specific clinical scenarios. Conclusions: Dietary interventions and ONS are valuable components of IBD management, offering benefits for inflammation reduction and nutritional optimization. Future research should focus on personalized nutrition approaches, standardized trials, and integration with pharmacological management to enhance evidence-based recommendations for IBD patients.