That's absolutely correct.  However, it's also true that a calorie is a calorie as far as your metabolism is concerned.  Calories are energy.  Nutrients are the ratios and types of chemicals we need.  Nutrients have a strong effect on satiety, making us feel full or hungry despite caloric intake/energy levels.  In fact many people are both fat, and critically malnourished in certain nutrients.  By eating high calorie low nutrition foods they are increasing the amount of calories they need to eat to reach certain minimum inputs for nutrients. If you eat home prepared whole foods in appropriate ratios it is difficult to over eat.  You just don't want to. Counting calories is like a tool to figure out what normal portions are when you switch to a healthy diet, or for making sure you don't over eat despite having a low nutrition high calorie meal on a particular day.