GLP-1.

Glucagon-like peptide-1, an incretin hormone affecting insulin and appetite.

GLP-1, or glucagon-like peptide-1, is an incretin hormone released by cells in the intestine in response to food. It stimulates insulin secretion in a glucose-dependent way, meaning it prompts insulin release when blood glucose is elevated and much less so when it is not, which is why this mechanism carries a lower risk of driving glucose too low than older insulin-releasing drugs. It also suppresses glucagon, slows gastric emptying, and acts on appetite-regulating regions of the brain to increase satiety. The native hormone is destroyed within minutes by the enzyme DPP-4, so the therapeutic class is built entirely from engineered analogs that resist that enzyme and are held in circulation by albumin binding, which is how a hormone lasting minutes becomes a drug given once weekly. GLP-1 receptor agonists are now a major class of metabolic medicine, and newer entrants combine GLP-1 activity with GIP or glucagon receptor activity in a single molecule. The point worth clarifying is that GLP-1 itself, the natural hormone, is not what anyone is taking. Products marketed by invoking the hormone's name are not equivalent to the analogs that carry the clinical evidence, and stimulating the body's own GLP-1 release is a different intervention from supplying a long-acting receptor agonist.