Evidence Explorer / MS-N021

Evidence at a glance

• Population: Adults undergoing gastrointestinal cancer surgery.
• Intervention: Oral or enteral formulas combining arginine, nucleotides and omega-3 fatty acids around surgery.
• Benefit: Meta-analyses of randomized trials report fewer infectious complications and a shorter stay.
• Boundary: Omega-3 alone is not equivalent, and no overall-survival benefit has been established.

What the human evidence found

A 2026 systematic review identified 90 randomized trials; 55 trials with 7,462 participants contributed to meta-analysis. Combination immunonutrition reduced odds of anastomotic leak (OR 0.62, 95% CI 0.50–0.76), respiratory infection (OR 0.46, 95% CI 0.33–0.64), wound infection (OR 0.67, 95% CI 0.46–0.98) and sepsis (OR 0.45, 95% CI 0.28–0.70). Mean hospital stay was 2.47 days shorter (95% CI 0.80–4.13 days shorter).

A 2019 review of 16 preoperative trials (1,387 patients) similarly found fewer infectious complications (OR 0.52, 95% CI 0.38–0.71) and a 1.57-day shorter stay, without a significant mortality difference. In those trials the active formula contained arginine, omega-3 fatty acids and nucleotides.

The 2026 analysis found omega-3-only formulas did not reduce morbidity. Product composition and timing are therefore part of the clinical question.

Limits and what this cannot establish

Trials span different cancers, operations, nutritional-risk levels, comparators and enhanced-recovery pathways. Pooled relative effects do not guarantee the same absolute benefit in every surgical program.

This is perioperative supportive care, not evidence that a supplement prevents recurrence or treats residual cancer.

Safety and practical context

Use should be coordinated by the surgical and dietetic team. Renal or liver dysfunction, fluid restrictions, allergies, feeding access and the operation planned can change suitability. Do not substitute a retail supplement for a studied formula.

The 2026 review reported no author conflicts; funding and product support across the 90 component trials were not independently re-extracted.

Questions for the care team

• Does the surgical pathway already include a specific immunonutrition formula?
• Am I nutritionally at risk, and when should feeding begin and end?
• Is the proposed product comparable with the arginine–nucleotide–omega-3 formulas studied?

Sources checked

• 2026 systematic review and meta-analysis (PMID 42331289)
• 2019 preoperative immunonutrition meta-analysis (PMID 30817349)
• ESPEN practical guideline: clinical nutrition in surgery (PMID 34242915)

Appraisal date: October 14, 2026. Last literature search: October 14, 2026.

Educational evidence summary, not medical advice. Research regimens describe what was studied; they are not personal prescribing instructions and should not replace cancer treatment or individualized supportive care.