Amino acids serve as the building blocks of proteins and peptides and are one of the skin's natural moisturizing factors (NMFs) - a group of substances that ensure moisture balance within the skin.
Amino acids are an essential element of healthy skin and work to optimize skin homeostasis, which maintains skin barrier function. Each amino acid will perform a different function for skin (e.g. hydrating, maintaining the microbiome or neutralizing skin damaging free radicals). Common amino acids seen in skincare include arginine, histidine, methionine, lysine, proline, leucine, glycine and glutamine.