Well, a calorie is simply a form of heat measurement. It is the amount of energy that is required to raise one milliliter of water by one degree Celsius. Calorie measures the amount of heat or energy that is released when you burn the food you have consumed.

Calories are actually burnt through a very complicated process that oxidizes food to its basic components. Take for example, if you burn sugar, the sugar will be transformed into carbon dioxide in a chemical reaction. However in the human body, the food burnt is converted to forms of energy.

So therefore when you consume food, the food is stored as body fat or glycogen (glycogen is mostly stored in liver and muscles) to be burnt for energy. Your body's preference is to burn glycogen first and then body fat when you expand energy such as when you are performing an exercise routine.

The more muscle mass you have, the more calories you will burn. This is because muscle cells are metabolically active where fat cells are not because fat cells do not have much function and they are not active. Fat cells just sits there making you look ugly and may cause health complications.

Different food category carries different amount of calories. For example, there are about 4 calories in a gram of protein or carbohydrate. However, each gram of fat contains 9 calories and so the more fat you eat, the more calories your body will store and you will have a harder time burning them off if you want to lose weight. Empty calories like alcohol should be avoided if you want to lose weight because each gram of alcohol contains 7 calories.

Some people raise their metabolic rate (calorie burning rate) by eating several small meals a day instead of usual three big meals. By eating more frequently, your insulin level is also regulated and less insulin will then be converted to body fat.

So how can you burn more calories and also raise your metabolism in order to be a natural calorie burner? The answer is to build more muscles, eat frequent small meals and embark on an exercise regimen to expand energy and thus burning more calories in the process. By doing so, you will be losing weight naturally in a healthy way.