From support to strategy: The evolving role of perioperative nutrition in regulating the prognosis of colorectal cancer surgery

The global burden of colorectal cancer (CRC) continues to rise, and the role of perioperative nutrition is shifting from "passive support" to an "active therapeutic" strategy. This narrative review synthesizes recent evidence on metabolic reprogramming and prehabilitation, immunonutrition and microbiome-guided approaches, enteral nutrition and long-term prognosis, and AI-enabled precision nutrition within CRC perioperative care. Findings indicate that multimodal prehabilitation-structured exercise combined with targeted nutrition-enhances metabolic flexibility, mitigates insulin resistance and inflammation, increases preoperative functional reserve, and improves postoperative complications and recovery trajectories. Immunonutrition (e.g., omega-3 fatty acids, arginine, glutamine) and probiotic/prebiotic interventions strengthen the intestinal barrier and recalibrate the immunosuppressive tumor microenvironment, with signals for reduced infections and overall complications. Enteral nutrition correlates with improved survival, while composite nutrition-inflammation indices (PNI, CONUT, GNRI) independently refine risk stratification and optimize prognostic modeling. Microbiome- and multi-omics-informed precision nutrition, supported by AI-based dietary assessment and dynamic monitoring, offers feasible pathways for individualized interventions. However, real-world implementation is constrained by under-recognition of malnutrition, resource limitations, and variability in Enhanced Recovery After Surgery (ERAS) adherence. Establishing nutrition as a strategic pillar of CRC perioperative management is evidence-based. Priorities include consensus-driven, operational evaluation and intervention workflows; clear population stratification and biomarker-guided decision criteria; and strengthened long-term follow-up and multidisciplinary collaboration to translate and amplify the metabolic and immune benefits into tangible clinical gains.