Incretin

Incretins are peptide hormones secreted by the intestine in response to food intake that amplify insulin secretion from pancreatic β-cells beyond what an equivalent intravenous glucose challenge would achieve.

The two principal human incretins are glucagon-like peptide-1 (GLP-1, secreted by intestinal L-cells) and glucose-dependent insulinotropic polypeptide (GIP, secreted by K-cells). Together they mediate the incretin effect — the greater insulin release from oral than intravenous glucose at matched glycaemia.