This definition below, although it might be true doesn't really apply to people who are overweight.
Most of us have never really felt hunger.
Hunger Pangs (also called hunger pains) are the result of an irritation of the lining of the stomach. When the stomach empties after the digestion of a meal, its walls come into contact and rub against each other. An empty stomach whose lining is not irritated will feel comfortable, but for an empty, irritated stomach, the rubbing of its walls will cause a painful, gnawing sensation. Because the gnawing sensation is relieved by eating food, which separates the walls of the stomach, the gnawing sensation is associated with hunger and is called hunger pangs. Hunger pangs are not true hunger, which is a physiological need for nutrients, accompanied not by pain but by pleasant sensations of desire. Hunger pangs are one of about ten forms of false hunger (read about other forms of false hunger) and are a cause of overweight because they prompt eating when there is no need for food. In fact, eating to relieve an irritation of a stomach deprives that organ of necessary rest and results in further irritation (a vicious cycle).
Most of us have never really felt hunger. This brings me to what is called false hunger
The Discomfort of the Body in Utilizing Reserves. When there is a deficit in caloric intake, the reserves of the body must be utilized to supply energy. This utilization can cause discomfort for the following reasons:
(a) The body is not practiced in accessing its own fat.
(b) The fat contains stored toxins, the release of which places a burden on the eliminative system.
Here, exercise is extremely important in cleaning out toxins and teaching your body to burn primarily fat instead of sugar. As you understand and apply that knowledge, your body will gradually learn to burn fat comfortably.