This section is from the book "The Hygienic System: Fasting And Sun Bathing", by Herbert M. Shelton. Also available from Amazon: The Hygienic System Vol III Fasting and Sun Bathing.
An important object secured by the fast is the rest of the organs of the body. The overstimulation of the physiological functions, which results from over-eating, weakens and impairs them through overwork. Fasting reverses this and permits them to recuperate. During the rest thus afforded, these organs are enabled to repair their damaged structures and restore their fagging energies, thus they are prepared for renewed function and are given a new lease on life. A fast is to the organs of the body what a night of restful repose is to the tired laborer.
Digestion and assimilation of food are a tax on the vital powers of the organism and increase the work of the stomach, liver, intestines, heart, lungs, kidneys, glands, etc. The more food eaten the more work these already overworked organs are called upon to perform. How can increasing the work of these organs help the sick? If feeding does not prevent sickness how may overfeeding restore health?
That fasting is a period of physiological rest was emphasized by all the early Hygienists--Jennings, Graham, Trall, etc. Thomas Low Nichols says: "in fevers and all inflammatory diseases fasting . . . . is a matter of the first importance. As a rule, nature herself points out this remedy. When animals have any malady, they stop eating. Loss of appetite is a symptom of disease, and it points also to the mode of cure. * * * Not only must the stomach have rest, but all the organs of nutrition, and the nerves which produce their action. When we stop food in fevers and inflammations, we diminish the volume of the blood and relieve the action of the heart; and by relieving the system of the labor of digestion and assimilation, we allow the nervous force to expend itself in recuperative action . . . . a cold is a sort of fever and there is no better remedy for a cold than abstinence from food." After pointing out that the loss of appetite seen in all acute diseases and common in chronic disease, is "the voice of nature forbidding us to eat," and lamenting the fact that physicians and nurses disregard this "voice of nature" and force food down the throats of "disgusted patients," Nichols says, "rest for the stomach, the liver, all the organs of the nutritive system, may be the one thing needful. It is the only rest we will not permit. . . In certain states of disease, the more the organs of digestion are weakened and disordered, the best beginning of a cure may be total abstinence from all kinds of food. There is no cure like it. If the stomach cannot digest, the best way is to give it a rest. It is the one thing which it needs."--The Diet Cure, 1881.
Dewey referred to fasting as the "rest cure," and said that rest "is not to do any of the curing (healing) any more than it heals the broken bone or the wound; it is only going to furnish the condition for cure." Here he was speaking of physiological rest or fasting. Mr. Carrington also insists upon the necessity of physiological rest in disease, but he stresses particularly rest of the digestive system, even prescribing forcing measures that prevent rest of other systems of the body. Both Tilden and Weger emphasized the fact that fasting is a period of physiological rest. Perhaps Walter stressed this fact more than anyone else.
I think it necessary to emphasize the rest that fasting affords to the other organs of the body and not overstress the rest of the digestive system. Let us take the heart: it is no uncommon thing to have patients come to us whose hearts are pulsating eighty or more times a minute against increased resistance. This is to say, the heart is rapid and the blood pressure is increased. The heart is slowly wearing itself out by this work.
I have seen many diseased hearts that were supposed to be "incurable" fully recover during an extended fast. A few years ago a business executive came to me for care. Repeatedly during the preceding two years he had been refused life insurance because his heart was diseased. One month after a forty days' fast he bought ten thousand dollars of life insurance.
The ductless glands, the respiratory system, the nervous system, in fact, the whole organism rests during a fast. The exception is the excretory system. This system does more work, at least through a large part of the fast, in freeing the body of its accumulated toxins. This inner rest, that is, this rest of the internal organs which fasting affords, is what is meant by physiological rest.
Rest! Where is there a rest like fasting? People go away for a rest. They get a change of scenery, a change of food, a change of activity, but they fail to secure the rest they need. If they would but fast a few days they would return to their old duties with renewed zest and increased energy. Nothing can give renewed power of digestion to a worn-out digestive system, nothing affords such rest to over-wrought nerves, to fatigued bowels, or to an over-worked heart and glandular system as a fast--physiological rest.
Most vacationists go away and increase their physical exercise and eat more because of increased appetite and come back worse than before. Physiological rest, decreased physical activity and long hours of recuperating sleep, will do more for these people in a few days, than months spent in the conventional manner.