Which would you prefer, a car with a full gas tank or an empty gas tank? Your answer is most likely a full gas tank. Did you know that your body has a gas tank? It does. The fuel that your body stores is carbohydrate. Carbohydrate is your body’s gasoline. It is the fuel that supplies your body's immediate energy needs. Most of your daily activities and exercise are fueled by carbohydrate. With this in mind, it should be obvious that you want to keep your gas tank full so that your body has energy.
When you're dieting, however, your gas tank is in jeopardy. Dieting is a state in which you are eating fewer calories than you're expending. In this situation, your body mobilizes its carbohydrate stores to make up for the caloric deficit. Carbohydrates, stored in your body, provide the energy that is missing from your diet. When the carbohydrate stores are raided, it will cause your body weight to plummet on the scale. This is due to the fact that carbohydrate, when stored, always bonds with water. Water is a heavy dense compound. When the carbohydrate molecule is called to provide energy, the water is sheared off and eliminated from the body. This loss of water weight leads to a false sense of accomplishment on the scale. You will think that you have lost fat when in reality you have only lost water. More importantly, you are now left with an empty gas tank.
An empty gas tank is a problem for several reasons. Number one, when your carbohydrate stores have been depleted, your body will be low on energy. This will leave you feeling tired and uninspired for exercise or other physical activities.
An empty gas tank may also slow your metabolism. Consider how you drive your car when you're close to running out of gas. Do you drive your car aggressively? Do you speed down the freeway and stomp on the gas when approaching the yellow lights? Probably not; unless you enjoy walking along the roadside carrying gasoline containers. Instead, you probably drive your car extremely conservatively. Driving well under the speed limit and gingerly applying the gas only when necessary. Do you want your body to respond in a similar manner when it's gas tank is empty? Of course not. We want the body's metabolism to be running at full speed. We want the body aggressively utilizing energy so that more weight can be lost.
The moral of the story is to avoid low carbohydrate diets. Also, incorporate a free-day concept in your dieting routine. Free days are days in which you consume whatever food you want, in whatever quantity you want, for the entire day, once a week. This will help keep your gas tank full and your metabolism high (yes, there is research that supports the free day concept in assisting weight loss). A full gas tank always beats an empty gas tank.