Calories, while a part of it, isn't the main factor in weight. How well and how quickly you metabolize what you eat and how much activity you engage in are more important. Counting calories doesn't really do you much good in the long-term if those calories are, say, in the form of foods that metabolize quickly into sugar -- if not burned off quickly they will store as fat. The best way to eat is to adopt a permanent diet made up of food you enjoy eating that is balanced appropriately between foods rich in nutrients and antioxidants such as vegetables and foods that provide energy such as complex carbs and foods that help build and maintain muscle tone, meaning protein. As for eating "unhealthy" foods, you haven't mentioned what foods you mean, but eating too strictly will increase stress, and that's not good, either -- you gotta enjoy your life.