Amino Acid Composition of Breast Milk from Urban Chinese Mothers
Garcia-Rodenas CL, Affolter M, Vinyes-Pares G, De Castro CA, Karagounis LG, Zhang Y, Wang P, Thakkar SK
Protein in breast is a key nutrient for supporting growth and development; it provides indispensable amino acids for protein building and can stimulate secretion of growth-promoting factors. Most amino acids in breastmilk are constituents of proteins, but there is a small amount found as free amino acid (FAA). This study analyzed total amino acids (TAA) and free amino acids (FAA) in breastmilk of Chinese mothers covering eight months of lactation. TTA decreased as lactation progresses, and the concentration of indispensable and dispensable amino acids was highest in early milk samples. Leucine and methionine were the most and the least abundant indispensable amino acids, respectively. FFA contributed to less than 2% of TTA, and were lower in early stages compared to later. Glutamic acid was the most abundant FAA contributing to 70% of the mass. The amino acid composition of breast milk in this study is comparable with other reports suggesting that it is an evolutionary conserved trait.
Nutrients. 2016 Sep 28;8(10). pii: E606