Fasting emphasises the principle of rest for the organs of digestion. As a system of therapy, it professes to set free the energy usually expended in digesting food for vital purposes, and to diminish the friction in the machinery of the organism by throwing off the waste matter accumulated by indulging in excess of nutriment. Its advocates assert that it is efficacious in restoring health without the necessity for having recourse to rest.

Forced feeding is the antithesis of this, claiming by an excess of nutriment and enforced rest to restore lost vitality, and in particular to give abundance of energy to those who have been too prodigal in its expenditure. The results of both methods of treatment are thus stated to be identical, but in every other respect the systems are hopelessly at variance.

Although it may be at once frankly conceded that the medical profession has practically no experience of the therapeutic value of prolonged fasting in disease, no array of scientific facts could so seriously menace its claims as the excellent results of treatment on the Weir-Mitchell plan. Employed in suitable cases, the latter can be credited with some of the most brilliant cures in the whole realm of therapy, although, strange to say, in one respect there is a great similarity between it and fasting.

Just as in the latter system the peccant material removed under its influence is stated to be an excess of nutriment, a condition quite unclassified and unrecognised by pathological anatomy, so in those cases in which the beneficent effects of hyperalimentation are most to be noted, viz., those of neurasthenia, pathologists have been unable to agree upon any alteration of the tissues to account for the disease.

In most cases, of course, there is a loss of fat and a considerable alteration in the quality of blood, but these are rather effects than causes. Whatever be the pathological anatomy of the condition, the real factor of importance is the daily expenditure of a greater amount of nerve force than can be manufactured to keep up the necessary supplies, and this in time so alters the whole nutrition of the nervous system that an efficient amount of sleep cannot be obtained to repair the daily waste. This in turn interferes with the digestive functions, impairs the quality of the blood, and the nerves of nutrition are still further exhausted, so that ere long a vicious circle is established which is most difficult to break. The only method whereby this may be accomplished is to improve the reparative processes of the body by restoring the sleep and digestive power, and reducing the expenditure of nervous energy to the lowest point possible; and the best means of effecting this is by the method now so well known as the "rest cure."

Application In Neurasthenia

It would almost appear as if a modified form of fasting, or at any rate its equivalent of chronic under-nutrition, were associated with the etiology of neurasthenia, and it is clearly a paradox that what is represented as curing so many forms of disease should, in some sort, be responsible for the production of a diseased condition closely allied to the alleged "cured " condition at the end of a prolonged fast. It is difficult in such circumstances to eliminate the mental influences in either case, so potent for good in fasting, so potent for evil in the production of neurasthenia.

Whilst the loss of fat is not in itself a pathological incident of much importance, its rapid replacement is a factor of great moment in nervous exhaustion. It is usually the first indication that the processes of repair are being restored, and probably it is some such conception as this which obsesses the average man with such a wholesome dread of losing his adipose tissue. Even when a man is frankly obese, and announces his desire to be relieved of some of his superfluous flesh, the reduction of a few pounds frequently makes him pause, as much from prejudice as from the remarks of his friends that he is getting thinner. His imagination is quickly overwhelmed with visions of the ravages of consumption, and he already considers himself the victim of this or some other disease connected with malnutrition. He has learned to associate loss of weight with loss of strength, and is unable to differentiate between a loss of what is simply an incubus and one which involves an encroachment upon his vital energies.

When the organs of assimilation are capable of renewing the supply - a supply which is doubtless being constantly consumed, and hence needs constant renewal - a mere loss of fat is a matter which we can afford to ignore. But when there is a persistent drain upon the subcutaneous layer of fat, we are in the presence of what may constitute a very real danger. It is then our duty to make an investigation into its causation, whether due to excessive loss or failure to furnish fresh supplies, so that we may be in a position to prevent any further encroachments on what is really a reserve of stored-up energy. We know from experience that when the daily supplies of fat cease to be replenished, the position is a grave one, as it is really only a question of time for the life stream itself to be attacked, and for some form of anaemia to supervene. Loss or gain of weight appears to synchronise with loss or gain of haemoglobin in the blood, and this hypothesis is by no means disproved by the existence of a class of fat anaemic people, usually women.

Full-blooded or plethoric people are generally stout, and, as a rule, thin-blooded people are thin. The occasional obesity of anaemic people has been attributed to lessened tissue combustion, and that again to a supposed diminution of the number of red blood corpuscles, but in all probability it is accounted for by some constitutional peculiarity in those in whom the percentage of haemoglobin is reduced. It is a well-known fact that bleeding used to be resorted to for the purpose of increasing the deposit of fat, as, after bleeding, a good deal less oxygen is absorbed from the pulmonary surface; but this is, of course, explicable by the reduced amount of haemoglobin, consequent upon the diminution in the number of the red blood corpuscles.