A pound of fat represents approximately 3500 calories of stored energy. In order to lose a pound of fat, you have to use 3500 more calories than you consume. Although this seems like a simple formula remember that your body is a thinking organism designed to protect itself.
If you were to try to reduce your intake by the entire 3500 calories in one day, your body would register some type of alarm and think that there is a state of emergency. Immediately your metabolism would slow down and no weight loss would be achieved.
It’s better to spread your weight loss out over a period of a week, so that you aim to reduce your caloric intake by 3500 to 7000 calories per week, resulting in weight loss of one to two pounds per week. It’s generally not recommended to try to lose more than two pounds in a week. Attempting to do so may cause health risks, and on top of this you’re unlikely to be successful.
In the example of attempting to lose two pounds per week, you can use a basic method of calorie counting to help you accomplish your goal. To do so, you need to figure out how many calories a person of your age, sex, and weight usually needs in a day, subtract 500 from that amount, and follow a diet that provides you with that many calories. For example, if you would ordinarily need 3000 calories in a day, you would follow a 2500-calorie a day diet. Next, figure out how much exercise a person of your weight would need to do to burn 500 calories per day, and engage in an exercise plan that will help you achieve your goal. The result is simple: 500 fewer calories consumed and 500 more calories expended equals a 1000 calorie per day deficit, which, over the course of a week adds up to 7000 calories, or two pounds. Although individual results may vary, the bottom line is if your body is consuming fewer calories than it’s expending, then weight will be lost.
HOW TO CALCULATE YOUR NEEDS
In order to eat fewer calories than you need, you have to determine how many calories you actually need. Adults can calculate their approximate energy needs using the following formula:
A. Body weight multiplied by 12 (for men) or 11 (for women) e.g., 150 lbs. x 12 = 1800
B. Activity One third body weight multiplied by the number of hours you don’t sleep, typically 16 hours 150 lbs. x 1/3 = 50 x 16 = 800
C. Required Calories A + B 1800 + 800 = 2600
Thus, we determine that a 150-pound man requires approximately 2600 calories per day. The “Basal Metabolic Rate” is the number of calories a man of that weight would burn just to keep the heart beating, the lungs pumping, etc. You would just burn your basal metabolic rate worth of calories if you slept all day. Thus the “Activity” calculation is approximately the amount of calories a person would expend by spending his or her whole day sitting around. If you are engaging in activities other than sitting all day, you can increase your activity hours by the number of hours you are actually active.
Adult females can calculate their approximate energy needs using the same formula, except that the “Basal Metabolic Rate” is determined by multiplying body weight times 11 instead of 12. Children and teenagers require more calories by body weight, but the amount varies by age and by individual child. It is best to consult a physician before altering a childs diet, however activity and exercise increases wont hurt the average youth of today, and will show some benefits of controlling obesity.
Overall, this gives you a general idea of what a calorie is, how it relates to weight, and how the body turns calories into fat. This is not of course a complete diet plan. However understanding your body is a definite prerequisite to making the changes necessary to conquer obesity.