Recent advances in critical care nutrition: from dose escalation to phase-guided and response-guided care

PURPOSE OF REVIEW: To critically appraise recent advances that are shifting critical care nutrition from uniform nutrient targets towards phase-guided, phenotype-guided and response-guided care, with particular emphasis on major studies published in 2025-2026. RECENT FINDINGS: Recent large trials do not support routine early full-dose energy or high-dose protein delivery in unselected critically ill patients, and some higher dose strategies have generated safety signals. Indirect calorimetry improves measurement of energy expenditure, but measured expenditure is not synonymous with the dose that should be delivered. Emerging data suggest that dynamic responses, including early phosphate trajectories, may help identify metabolic readiness for feeding, although no validated bedside marker exists. Pharmacological intravenous vitamin C has shown no benefit and recurring harm signals in shocked patients, whereas micronutrient care should distinguish physiological requirements and deficiency correction from megadosing. After ICU discharge, intake frequently falls during the transition from enteral to oral nutrition, and intake-guided protocols have achieved high nutritional adequacy in proof-of-concept studies. SUMMARY: Critical care nutrition is moving from universal targets towards phase-guided, phenotype-guided and response-guided treatment. Acute-phase caution should not become prolonged underfeeding; repeated metabolic assessment, body composition, reliable intake monitoring and continuity through recovery are central priorities.