Which 3 amino acids are actually given in smaller amounts to neonates compared to adults?

• A. Phenylalanine
• B. Methionine
• C. Glycine
• D. Phenylalanine, Methionine, and Glycine

Answer: (D)

Neonates have different amino acid needs than adults because their organs and metabolic pathways are still maturing, which affects how they process and tolerate certain amino acids. In neonatal nutrition support, some amino acids are provided in lower amounts to avoid overloading immature systems while still supporting growth. Phenylalanine and methionine are essential amino acids whose clearance and metabolism can be limited in newborns, so limiting them helps prevent buildup and metabolic stress. Glycine, though nonessential, is also kept in smaller amounts in neonates to align with their developing capacity to use it and to avoid excess nitrogen load. For these reasons, all three—phenylalanine, methionine, and glycine—are given in smaller amounts to neonates compared with adults.