So long as there are enough fuel and food, but not too much, and so long as all the debris is carried away, there is health. But let this process be thrown out of balance and there will be disease. The food intake is seldom too small, though the digestion is frequently so poor that not enough good food gets into the blood. Old age is largely due to overeating and eating the wrong kinds of food. This is how overeating causes premature aging, when it does not kill more quickly: When too much food is taken, too much is absorbed into the blood, provided the nutritive processes are active. Then all the food in the blood can not be used for repair and fuel. The balance must either be excreted or stored away in the body as deposits. If this storing takes place in the joints, the result may be rheumatism or gout and at times even a complete locking of the joints (anchylosis). If it is stored in the walls of the blood-vessels they become hard and unyielding. No matter where deposits take place, some of them will be found in the walls of the blood-vessels. When these vessels grow hard they decrease in caliber. The result is that the heart is compelled to work very hard, but even then enough blood is not forced through the vessels. The circulation becomes sluggish. The blood in the various parts becomes stagnant. Then insufficient good oxygen and first-class nourishment are brought to the parts and not enough waste is carried away. Now the billions of cells of which the body is composed are constantly bathed in poisonous blood. The result is lowering of physical tone, or degeneration, of the whole body. The hands and the feet suffer most at first from the poor blood supply and become cold easily. Those who suffer constantly from cold hands and feet should know that they are aging, although they may be but twenty years old. Such a condition as this often gives rise to varicose veins in the legs. The feet are so far away from the heart, and it is such a long upgrade return of the blood, that the circulation in the lower extremities easily becomes sluggish. The flabby, relaxed tissues and the hardened blood-vessels allow the blood to stagnate. This is why senile gangrene is so common in the feet and so often fatal.