Gut-brain communication in appetite regulation involves stomach distension, the rate of rise of blood glucose, and gut hormones like cholecystokinin.

“A number of factors play into it distension of the stomach being one so that as the stomach is pushed out it tends to cause satiety and decrease your urge to eat another factor is not the level of blood glucose but the rise of blood glucose the ascent of it and these factors are sensed one by receptors within the gut which sends signals to the brain and the other cells within the brain that are chemosensitive and detect nutrients within the gut another factor which you alluded to before are the endoendocrine cells within the gut which make hormones such as cholecystokinin which can signal to the brain by going through the blood-brain barrier to be received by neurons”