A peptide is a short chain of amino acids linked together, smaller than a full protein. GLP-1, GIP, and glucagon are all naturally occurring peptide hormones, and GLP-1 medications (semaglutide, tirzepatide, liraglutide, etc.) are themselves synthetic peptides engineered to mimic and extend the action of these natural hormones in the body.
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Peptide
Updated Jul 14, 2026