Calorie Secrets states that 1 pound of fat is equal to 3,500 calories. Therefore, in order to lose 1 pound of body fat you must burn 3,500 more calories than what you consume.
According to Good Housekeeping, everything a person does, including smiling and blinking, utilizes calories. Determining the amount of calories burned by any one person is based on a variety of factors, such as weight, height, activity level and even metabolism. By increasing activity and cutting calories, a person who burns 500 more calories per day than what he eats can average a weight loss of 1 pound per week.