Fasted and low-carb states lend themselves to alertness. Carb-rich states lend themselves to calmness and sleepiness.

There are endokrine signal involved to signal hunger and satiety. The archuit nucleus release chemicals that act as brakes and accelerators of hunger. - The PMOC neurons (system) produce a-MSH, which reduces appetite and get active while eating. They are activated by ultra-violate light to the eyes, which explains the lower hunger and appetite in... See more