Amino acids and lean mass accretion in preterm neonates

Authors: RAMOS DOS SANTOS, ANTONIO - Texas A&M Agrilife; FIOROTTO, MARTA - Children'S Nutrition Research Center (CNRC); DAVIS, TERESA - Texas A&M Agrilife

Submitted to: Current Opinion in Clinical Nutrition and Metabolic Care
Publication Type: Review Article
Publication Acceptance Date: 12/29/2025
Publication Date: 1/1/2026
Citation: Ramos Dos Santos, A.C., Fiorotto, M.L., Davis, T.A. 2026. Amino acids and lean mass accretion in preterm neonates. Current Opinion in Clinical Nutrition and Metabolic Care. 29(1):89-97. https://doi.org/10.1097/MCO.0000000000001178.
DOI: https://doi.org/10.1097/MCO.0000000000001178

Interpretive Summary:

Technical Abstract: Purpose of review: This review evaluates recent evidence on how total protein and energy intake, amino acid composition, and nutrient delivery modality influence protein synthesis in preterm neonates, with the goal of informing nutritional strategies to support optimal lean mass accretion and growth.Recent findings: Preterm neonates exhibit anabolic resistance to feeding due to impaired insulin and amino acid signaling in skeletal muscle. Enteral nutrition, especially fortified human milk, supports better lean mass accretion and neurodevelopment than parenteral nutrition. Intermittent bolus feeding and pulsatile leucine supplementation during continuous feeding further enhance mTORC1-dependent translation initiation signaling and protein synthesis efficiency in skeletal muscle, offering promising strategies to optimize lean tissue growth. Summary: Strategies that prioritize early enteral feeding, appropriate milk fortification, and nutrient delivery patterns that mimic feeding pulsatility may overcome anabolic resistance and enhance lean mass accretion, supporting healthy growth trajectories in preterm infants.