system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:Why do you start to feel less hungry after not eating for longer?

If you haven't had breakfast, and it's 11:00, your starving. However, at least for me, it gets to a point where I start to feel less hungry. If I haven't eaten for 20 hours or more, I feel almost not hungry at all, compared to how starving I was a matter of a few hours ago. Of course, when I see food, I'll eat it, but I still don't feel that total ravenous hunger that I did at peak hunger, and now, despite going longer without food, I feel only mildly peckish. What's going on?
gpt
Your body releases a hormone called ghrelin that makes you want to eat. This can be triggered by several things, including the time of day , or when your stomach is emptying. If you don't give in to its hunger urges, it will work its way out of your system.

After not eating for a while your body will start taking energy from glycogen reserves in your liver and muscles. After that, it moves from stored fat in your body instead, which will give you some energy and cause you to feel less hungry as well.

[EDIT: Added the step with glycogen reserves]