After we have broken down the protein we eat into amino acids, what happens to the amino acids and where?

When you eat high-protein foods, your body breaks down protein into amino acids and peptides through the action of digestive enzymes, such as pepsin. At the same time, your pancreas produces trypsin, chymotrypsin and other chemicals that aid in protein digestion.

Pepsin is the primary enzyme responsible for digesting protein. When it acts on the protein molecules, it breaks the bonds – called peptide bonds – that hold the protein molecules together. Next, these smaller chains of amino acids move from your stomach into the small intestine where they're further broken down by enzymes released by the pancreas.

Your small intestine contains finger-like extensions called microvilli. These structures enhance its ability to absorb dietary nutrients. When amino acids reach the small intestine, they're released into the bloodstream and used for various biochemical reactions.

Each amino acid has a different role in the human body. Upon absorption, some amino acids are incorporated into a new protein. Some fuel your muscles and support tissue repair. Others are used as a source of energy.

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