The GIP Pathway

The forgotten incretin: fat metabolism, energy expenditure, and the agonism debate

The Forgotten Incretin

For decades, GIP was dismissed as the "fat-storing hormone" -- the opposite of what you'd want in an obesity drug. Then tirzepatide showed that GIP agonism actually enhances weight loss when combined with GLP-1. This unit unpacks the biology behind this paradox and explains why both retatrutide and tirzepatide include GIP receptor activation as a core mechanism.

Trace the GIP Signaling Cascade

Follow GIP receptor activation through its downstream effects on fat metabolism, insulin secretion, and energy expenditure.

interactive GIP signaling cascade

Knowledge Check

Test what you've learned about the GIP receptor pathway.

Practice Exercises

Reinforce your understanding.