Aspartame helps you to keep in shape. The Calorie Counter below calculates how much weight you can lose by simply replacing some common foods and drinks with their lower-calorie alternatives, whilst otherwise maintaining your normal diet. Print your calorie savings! Print a blank calculator How do we calculate pounds lost per year? As a general rule, 3,500 calories equates to about one pound of body fat. Therefore, losing a pound requires a 3,500 calorie deficit. This deficit may be achieved by increasing activity/exercise, reducing calories in the daily diet, or ideally a combination of the two. For purposes of the "pounds lost per year" in this chart, it is assumed that activity levels are held constant.