The GIP signal

Tirzepatide binds the GIP receptor as strongly as the body's own GIP. GIP is the gut hormone released from K cells in the upper small bowel after food. In fat tissue, GIP signalling improves blood flow and helps fat cells take up and safely store fat, so less of it spills into the liver and muscle. In the brain, GIP receptors sit in the same appetite centres as GLP-1 receptors and calm the nausea signal, which is part of why the dual signal is easier to carry at high strength.