Your stomach growling isn't hunger — it's a negotiation between a dozen competing hormones, old evolutionary code, and a gut microbiome that may have its own agenda. This episode tears apart the calorie-in-calorie-out model not to replace it with pseudoscience, but to show you what the actual appetite regulation research looks like — and why ghrelin gets all the press while peptide YY quietly does the real work. If you've ever eaten a full meal and still felt weirdly unsatisfied, this one explains why.