In fact, according to physicians, the functioning of the digestion depends less on the brain than on hormonal mechanisms and autoregulators. However, during a fast, the digestive system gets an increasing rest. About ten hours after a meal, the contractions stop and the feeling of hunger disappears; five or six hours later the glucose stops coming directly from the intestines and begins to produce itself from the reserve of glycogen contained in the liver. From then on, the body works on itself in a closed circuit, becoming itself the source of the energy it uses. Instead of destroying an appropriating to himself nourishment taken from outside, man enters a state of nonviolence and detachment relative to the outside world.
Adalbert De Vogue