20 minutes after you eat, how do you feel? Is your energy zapped? Do you feel bloated, tired or uncomfortable? Do you feel like going for a walk or moving around? If so, you probably ate the right sized portion/meal. You ate until satisfied. However, if you are uncomfortable or tired, chances are you overate!
If this is your typical feeling...bloat, tired, uncomfortable after meals, next time try to have a little less and progressively make the meal size smaller until you feel energized 20 minutes after eating. Once you get there you will know that you are at a place where you are eating the right amount of food.
Also, remember the quality of food matters, as well. Eat healthy, portion controlled meals and eat until you are satisfied...not until you are full!