Multiple reviews have examined the impact of nutritional interventions in patients with burn injuries; however, discrepancies among results cast doubt about their validity. We implemented this review to assess the impact of various nutritional interventions in adult patients with burn injuries. We conducted a thorough search of PubMed, Scopus and Web of Science databases until 1 August 2024, to identify relevant meta-analyses of intervention trials, examining the impact of nutritional interventions on burn patients. We adopted the random-effect models to determine the pooled effect sizes while employing the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) to examine evidence certainty. Thirty-three original intervention trials from eleven meta-analyses were entered in our review. Early enteral nutrition could substantially reduce overall mortality (relative risk (RR): 0·36, 95 % CI: 0·19, 0·68, GRADE = moderate certainty), hospital stay (mean difference (MD): −15·3, 95 % CI: −20·4, −10·2, GRADE = moderate certainty) and sepsis risk (RR: 0·23, 95 % CI: 0·11, 0·45, GRADE = moderate certainty). Glutamine showed a notable decrease in the length of hospital stay (MD: −6·23, 95 % CI: −9·53, −2·94, GRADE = low certainty). However, other nutritional interventions, including combined immunonutrition, branched-chain amino acids, fish oil, ornithine α-ketoglutarate and trace elements, did not significantly affect the assessed clinical outcomes. Early enteral nutrition might impose a beneficial effect on mortality, hospital stay length and incidence of sepsis with moderate evidence. Lower length of hospital stay was also seen in burn patients supplemented with glutamine, although the evidence was weak.