Nutritional interventions in cancer management: a comprehensive scoping review.

Background: Malnutrition and treatment-related catabolism undermine outcomes in oncology. This study aimed to characterize nutritional modalities, outcomes, and contextual effectiveness in cancer management. Methods: Following a predefined scope, a comprehensive search was conducted across three academic databases to identify relevant literature. Eligible study designs for inclusion were randomized controlled trials, pilot/feasibility studies, and matched cohort studies in adults with cancer that reported patient/clinical outcomes. Data were charted on population, intervention components, comparators, outcomes, feasibility, and further synthesized narratively. Results: Fifteen studies conducted in countries such as Canada, Japan, Mexico, Spain, and India were included. The interventions were clustered as follows: (i) dietitian-led counselling with quantified energy/protein targets; (ii) oral nutrition supplements such as whey protein, ω-3/EPA-enriched formulas, and adapted foods; (iii) dietary patterns (modified Atkins); and (iv) multimodal prehabilitation including nutrition plus exercise/psychosocial, and sometimes anti-inflammatory medication. During chemotherapy, eicosapentaenoic acid (EPA)-enriched oral nutritional supplementation (ONS) improved appetite, intake, and treatment tolerability, whereas survival remained unchanged. Cachexia programs were feasible and safe, but adherence to supplements lagged behind exercise and medication. Culturally appropriate foods were also found to enhance acceptability and quality of life. Conclusions: Nutritional therapy is a feasible and clinically meaningful component of cancer care. Impact varied by context and fidelity; however, harmonized outcomes, adherence optimization, and cost-effectiveness data are needed to inform commissioning, scale-up, and evaluation strategies.