We may for our purpose divide all diseases into two classes, for in these groups the diet is quite different. One, in which the disease is of an acute character and lasts only a short while. In the second group, we have to deal with chronic conditions, or diseases lasting over long periods.

We will start to-day with the diseases of short duration. Here the main point is to see that the digestive tract is not burdened with much work. The principle of rest plays the greatest part in any disease, especially in regard to diet. In any disease, no matter what - of the stomach, liver, kidneys, lungs - the organism requires rest. You have, for instance, a patient with pneumonia. He has been all right, right along, but now he is attacked with pneumonia. Here it would be wrong to prescribe plenty of nourishment, He does not need it, and you would only make him worse if you force him to take food. Nature has provided for that, and gives hints in regard to the method of procedure. When a man is taken sick, he suddenly loses his appetite and has an aversion for food, and tells you to leave him alone. That is what nature does, and it is the correct way. His body is in good nutrition, and no harm is done if in that period of sickness - which usually lasts from three to six or seven days - he does not have food. His organism has enough material in it to utilize during that period of emergency. It is rather best to act on the principle of rest and not to burden the system with food that is not essential. Keep such a patient quiet in bed, with cold ablutions of the body or something of that sort; and left alone, the organism has a good chance to fight the disease. This principle prevails everywhere in all diseases. The patient may lose say eight or ten pounds during the disease, but as soon as the period of fever or the acute stage is over, the appetite will come back, the patient is hungry - even more so than formerly - he eats more and quickly replaces what was lost.

But while it is not essential to introduce much food into the organism during the period of acute illness, it is essential to look out for the amount of fluids in the system. You must not say: "Give the patient nothing" - that is wrong; but you must see that he gets enough water. That is a very important point. The reason for that is that a man in good condition - a normal individual, a healthy man - if deprived of food but supplied with water, can live for twenty or thirty days upon the material supplied from the body. There are professional starvation men who practice that, and have been able to live thirty or forty days on water alone using their bodies to live upon. At the end of that time, they resume eating and are again all right. If in addition you take away water, however, the period of life is shortened. One can live only three or seven days at the utmost without water. Why cannot a man live a little longer? He has enough in his body to live upon; there is enough flesh and fat in the body to live upon, and yet he dies. The reason for that is that there is a shortage of water, of fluids, in the system. We use up a great deal of fluid, by respiration, perspiration, by excretion through the kidneys, etc. We lose at least two or three quarts of fluids daily in this way. If it is not there, the organism takes it from the fluids in the system, the tissues dry up, the blood thickens, and the man dies. In two days we lose six quarts, that is twelve pounds from the fluids. Then what happens? There is plenty of nutritive substance in the organism, but the blood has become thickened, the capillaries cannot work, the substances which are in the system cannot replace those which are needed, the traffic is cut off, the rivers are dried up, the vessels cannot go, and the man dies. He dies not so much from lack of food material as from lack of fluids.

In the acute diseases, the loss of fluids is increased. During fever a patient, instead of losing three quarts of fluid a day loses four or five. If you do not see that the patient drinks, or that something is given him to replace the loss very quickly, there will be something wrong. So, while it is not necessary to introduce much food into the system during an acute illness, the necessity of introducing fluids is increased.

There is another reason why fluids are essential during the acute stage of disease. In most instances we have to deal with infections, and there are toxic substances developed through the system by bacterial action. These have to be removed from the system, and we can do this quickly if we flush the system. Give them more water than they need. They have to pass more water, and the water must reach the circulation first before it is carried off, and that washes out the system.

I will give you one instance of this, for I think that those things which really occur impress us more than anything else, so I will tell you of something that happened to me. When I was a little boy, I was in Russia, visiting some relatives, and cholera developed there. They were anxious to send me home, as was quite natural, and the carriage was waiting for me downstairs, so I put on my overcoat; but while I was getting ready to go down, I collapsed and was attacked with the cholera, and became unconscious, vomited, etc. I had the real Asiatic cholera, so I was put to bed. I could not talk, could not do anything. There were several physicians in attendance, and they thought I was going to die. They did not give me anything; at first I was kept without anything, but when I returned to consciousness I was very thirsty, as was quite natural, but the two physicians thought differently. They called in a third physician, and he said "Give him water; if he is thirsty, let him drink." So they put a big pitcher of water next to my bed, and I emptied it once, a second, a third time. I was drinking all the while. After a period of a week or ten days, during which I was almost dead, I began to recuperate, and you see I am still living. I think that water saved my life at that time. I am quite sure that if it had not been given to me I would not have had a chance of recovery. I want to impress upon you the necessity of giving liquids. If a patient is thirsty, let him drink. But supposing he is not thirsty, is apathetic, does not want anything, lets himself go. Is it necessary to remind him? I think it is. You must look out, even then. The fluids should be given; he should be encouraged to drink; give lemonade, Apollinaris water, barley water, etc., make him drink. If you cannot accomplish that, introduce the water into his system in some other way; through the bowels is a very good way. Give him saline injections. If he does not keep that and is very weak, and does not drink, and there is need of fluid, you can give injections subcutaneously, under the skin, but see that there is enough fluid in the system, especially in such conditions as diarrhea, vomiting, etc.

The principle of introducing liquids into the system to cover the loss from perspiration, etc., is of the greatest importance. While, as I have said, it is not essential to look out for the nourishment of patients in these acute illnesses, there are exceptions to this rule. For instance, you may have to deal with an elderly individual, say a patient of seventy or seventy-five. Usually such patients are not so very well nourished, people of this age usually grow thin, and cannot stand much loss, and there we cannot neglect to pay attention to the food, even in that short period, but see that they take food that is easily digested. Give them milk, say every two or three hours, decoctions of barley water, etc. Long ago Hippocrates understood this, and gave his patients the ptisan, which is a decoction of barley water and sugar. Sugar is a good nutritive material. He treated febrile cases by cutting off food and giving them barley water and honey.

For the next lecture we will take up the second group of diseases, and we will consider first the subject of diet in more prolonged acute diseases, such as typhoid fever, etc., and in chronic diseases.