If you go on a Very Low Calorie Diet(usually in the range of 400-700 calories or less a day), your body goes into starvation mode, thinks that there must not be enough food to go around so no need to feel hungry. That might be what you're referring to as fasting should have the same effect. I haven't heard of the effect continuing after starting to eat 1000+ calories a day again though, so I'd need to see some data on that.