Carbohydrates are the body's A-grade fuel source. Although both fat and protein can be used as an energy source, they are far less efficient than carbohydrate. Severely restricting carbs, then is never a good idea. It will adversely affect both your physical and mental energy levels.

Carbohydrate is the limiting factor in exercise. If you don't replace muscle glycogen, which is quickly burned through a work-out, you will hit the wall and your performance will quickly go downhill. So, even though restricting carbs may help to lose fat, it is not a healthy practice and should be avoided.

All of the carbohydrates that you eat will eventually end up in your bloodstream as glucose or blood sugar. All carbs, however, are not created equal. Some are good and some are bad. The good ones will help you to get lean, toned and tight. The bad ones will pile on the fat, lead to all manner of health problems and do absolutely nothing for you nutritionally.