If you do it right, you can lose weight without being hungry all the time. The key is to run a moderate calorie deficit, eg, 500 calories a day, and eat often so you aren't hungry. High fiber food and protein also help curb hunger. Tracking calories help you learn how much to eat and control portions. It's easy to overeat if you exercise a lot. That's partly because it can stimulate hunger but also because many of us (me included) tend to think you can eat whatever you want because you exercised. You can't, if you want to maintain or lose weight.