You get to know yourself well after about 5 days of zero food..... :))

I did that, and it helped to kickstart further weightloss. I was surprised how fast my body got rid of stored water, and how quickly I lost fat in the upper body region, primarily around my face, neck and shoulder.

Even much shorter fasts help you to understand how unimportant and fleeting a lot of feelings of hunger are. You get hunger pangs and feel like you need to eat, but in a hour it has passed and you go another 8+ hours just fine. When I eat some crappy food, I know it is going to make me feel very hungry in a few hours, but when it happens, I know it isn’t a real need and it helps stop the cycle of bad eating/overeating.

I'm not religious at all, but I still sometimes practice Ramadan for this reason. On top of the communal experiences of charity and shared meals that are more present during the month, the reminder that my body is greedy for food and does not really need so much is such a good annual reminder to have.