Application of the Crohn's Exclusion Diet in Patients with Crohn's Disease: A Scoping Review

Crohn's disease (CD) management requires sustainable dietary strategies. The Crohn's disease exclusion diet (CDED) combines partial enteral nutrition with exclusion of proinflammatory foods as an alternative to exclusive enteral nutrition. This scoping review synthesizes evidence on study characteristics, protocols, efficacy, and controversies of CDED. Following PRISMA-ScR guidelines, we systematically searched 7 databases from inception to 31 July, 2025. Original studies involving CD patients consuming CDED were included. Data extraction covered study design, intervention protocols, and outcomes (clinical remission, inflammatory markers, nutrition, microbiota, adherence). From 1001 records, 22 studies were analyzed. CDED protocols included 2-phase (strict/maintenance) and 3-phase (adding flexible maintenance) approaches. Clinical remission rates reached 70%-94% in pediatric and 45%-83% in adult patients. Inflammatory markers (C-reactive protein, fecal calprotectin) and nutritional indices (BMI, albumin) improved significantly. Gut microbiota beneficially shifted. Short-term adherence was high (≥85%) but declined long-term. Endoscopic remission (Simple Endoscopic Score for Crohn's Disease score ≤2) was achieved in 50%-54% of patients. Limitations included small sample size, regional evidence imbalances, and a lack of data on special populations, long-term outcomes, and underlying mechanisms. CDED effectively induces and maintains remission in CD, with efficacy comparable to exclusive enteral nutrition but better tolerability. Key future directions include optimizing study protocols, reaching broader patient groups, boosting long-term adherence, and combining therapies for more tailored management.