How Amino Acids Are Absorbed?

Amino acids, not proteins, are absorbed; proteins rely on prior digestion to amino acids. Most absorption of amino acids occurs in the jejunum; there is a lesser contribution from the ileum. Amino acids are absorbed by a co-transport mechanism with sodium ions.

How are amino acids absorbed in the body?

In adults, essentially all protein is absorbed as tripeptides, dipeptides or amino acids and this process occurs in the duodenum or proximal jejunum of the small intestine. The peptides and/or amino acids pass through the interstitial brush border by facilitative diffusion or active transport.

How are amino acids absorbed by a cell?

Amino acids are absorbed via a Sodium cotransporter, in a similar mechanism to the monosaccharides. They are then transported across the basolateral membrane via facilitated diffusion.