The average, healthy-weight person has about 112,000 calories stored in fat. Fat is a nutrient, and the body needs it for absorbing some vitamins, protecting internal organs, aiding in hormone and immune function and for energy The problem occurs when fat gets out of balance. Having too much fat in your body increases your risk for sleep apnea, high blood pressure, high cholesterol, stroke, heart attack, diabetes, inflammation and certain cancers. The formula for reducing fat is simple and straightforward, however difficult it may be to accomplish practically. You must expend more energy than you consume.

Fat Is Not Destroyed

You don’t burn fat in the sense that you are destroying it. By the law of conservation of mass, matter is neither created nor destroyed, but it can change in form. When you burn fat, you’re changing its form, making it useful for the body to use as fuel. The body prefers other fuel sources first, such as sugar, and will resort to using fat only after a number of other processes have taken place.

Exercise Helps Reduce Fat

Getting fit will help you burn fat. Exercise, such as cardiovascular conditioning and strength training, helps your body reduce fat through a number of mechanisms, in part because it increases the rate at which oxygen is delivered to your cells. In “You on a Diet,” Drs. Roizen and Oz state that doctors can tell how well your body is burning fat by measuring your breathing. The deep breathing caused by exercise gives your body the oxygen it needs to take care of all its energy needs. In addition, all physical movement burns calories, even daily activities like gardening and housework. Exercise that favors muscle strengthening, like weightlifting, running and martial arts, is particularly beneficial. Muscles constantly feed on calories. Every pound of muscle burns about 40 to 120 calories per day, making it crucial to maintain your muscles as you age, because you need to eat fewer calories to avoid gaining weight.

Total Calories Are More Important Than Fat

According to the National Academy of Sports Medicine, body fat reduction is achieved by total calories, not the amount of fat burned. Your body draws on calories from fat, carbohydrates and protein to meet its energy needs. The amount of calories the body will use from each of these nutrients depends on which of the body’s four energy systems it is using at the time. The body’s fat-burning system, aerobic lipolysis, is the slowest of all. This means your body will go through other sources of energy before it will tap into fat.

Fat Burning Is More Like After-burn

Because the body takes so long to get to fat, you actually cannot rely on it to burn fat during exercise. The reactions taking place after you exercise launch the attacks on your body fat. According to Dr. John Hussman, of Hussman Fitness, if you exercise at an intensity so great that you burn through your body’s other preferred fuel sources during your workout, your body will begin to mobilize fat afterward to continue taking care of all of its energy needs. It can go on burning fat for energy for up to 21 hours after your workout.

Foods Don’t Really Burn Fat

Ignore the claims that eating certain food will “turn on” your body’s fat-burning system. Generally, these diet plans work temporarily by severely limiting the total calories you eat, but in the long run are not sustainable. Burning through the food you eat, in the process called thermogenesis, however, will burn calories. Storing, digesting, absorbing and transporting food account for about 10 percent of the calories your body burns each day, according to the Mayo Clinic website, and that percentage is nearly impossible to budge.

Hormones Influence Fat Burning

According to “You on a Diet,” hormones for the thyroid and adrenal glands affect your body’s fat-burning ability. Too little thyroid hormonal activity will slow down your metabolism. Chronic stress will cause the adrenal glands to overproduce cortisol, which will stress your kidneys, force you to retain salt and water and slow down fat metabolism. A blood test by your health care provider will tell you whether your hormones are in balance.