Equally striking is the effect of anger on the liver. One most important function of the liver is to store glycogen, or "animal starch," which is a source of energy when liberated from the liver into the blood in the form of sugar. Under normal conditions, an exceedingly small amount of sugar--all the body requires--is liberated. The liberation of a greater amount is a waste; and, if long continued, its excessive liberation has a fatally weakening effect on the system, constituting the serious disease known as diabetes. Now, as has lately been proved by an American investigator, Doctor W. B. Cannon, of Harvard University, anger, or strong emotional excitement of any sort, immediately causes the liver to liberate sugar in excess. Doctor Cannon found this to be true in the case of both animals and human beings. Almost always a man examined after he had been angry or excited showed clear indications in the liquids of his body of glycosuria, or excessive sugar. Here is Doctor Cannon's summary of one of his most interesting observations: "C. H. Fiske and I examined twenty-five members of the Harvard University football squad immediately after the final and most exciting contest of 1913, and found sugar in twelve cases. Five of these positive cases were among substitutes not called upon to enter the game. The only excited spectator of the Harvard victory who was examined also had a marked glycosuria, which on the following day had disappeared."[6] Further than this, on testing the blood of excited and angry animals and people, Doctor Cannon discovered that it held in excess another substance which, like sugar, is usually present in the circulation in exceedingly minute quantities. This substance, called adrenin, has some extraordinary properties. It is secreted by two small glands back of the kidneys. If artificially extracted and injected into the blood of a human being in any appreciable amount, it instantly has the effect of creating a sharp rise in blood pressure, the blood vessels being constricted and the heart beat appreciably increased. It also alters the distribution of the blood, driving it from the abdomen to the head and limbs. And for the time being it enormously increases muscular power and abolishes all feeling of fatigue. Exactly similar effects, scientific research has proved, are brought about by the quantity of adrenin set free in the blood during periods of anger or other emotional stress. That is to say, not only does anger temporarily stop stomach action and abnormally stimulate the sugar-releasing function of the liver: it also imposes an unusual strain on the heart and the blood vessels. Likewise with worry. It affects the heart, blood vessels, liver, and digestive organs as anger does. Even in the lower animals, and when occurring in comparatively slight degree, worry puts a stop to stomach movements and digestive secretions. Thus, in discussing with me the physiology of worry, Doctor Cannon stated: