JenMemphis said:The food noise came back three weeks after I reduced my dose, well before the weight moved, which tells me something about which effect tracks what.
Central vs peripheral GLP-1R signaling in food noise: elegant studies using brain-penetrant vs peripherally-restricted GLP-1 agonists show that ~80% of the weight loss effect is centrally mediated[1].
The key brain regions: arcuate nucleus (appetite), area postrema (nausea), NTS (satiety), VTA/NAc (reward). Peripheral effects (gastric emptying, insulin secretion) contribute but are secondary for weight loss.
This has implications for next-gen drugs: optimizing brain penetration and CNS receptor occupancy may be more important than systemic exposure.
[1] Secher A, et al. J Clin Invest. 2014;124(10):4473-4488.