Physiological Action

The physiological effects of alcohol may be considered under several headings:

I. Action as a Food. II. Action as a Stimulant to the Nerves and Circulation. III. Action upon the Muscular System. IV. Action upon the Body Temperature. V. Action as a Diuretic. VI. Action upon Mucous Membranes. VII. Action upon Gastric Digestion. VIII. Alcohol Absorption - Hypodermic Use. IX. Elimination of Alcohol. X. Alcohol Poisoning. XL Alcohol and Climate.

I. Action As A Food

As a food, alcohol adds to the nutrition of the body by its prompt absorption, requiring no preliminary preparation by the digestive organs, which are therefore not taxed in any degree, and it is immediately conveyed in the general circulation to the liver and other parts of the system. The chemical changes involved in the assimilation of this form of hydrocarbon are but ill understood. Alcohol, even when digested in very large quantity, does not reappear to any extent unaltered in the urine, and, if not taken in excess, it is not exhaled from the breath, demonstrating that its combustion is complete. This combustion results in the formation of water and carbon dioxide. The fact that the body weight may increase under its use, and that the storage of fat in the tissues may be also increased even to an abnormal degree, does not absolutely prove that the alcohol itself has entered into their structure. Its action may be exerted through modification of oxidation processes or by preventing the burning up of other food materials, which are thereby enabled to be themselves added to the protoplasmic elements of the body; yet there is reason to believe that while the latter is the chief effect of alcohol as a food, it also may be directly stored in the body in the form of some other product, although this has been denied by M. Chauveau. Whatever controversy still exists over the physiological effect of alcohol as a food, it is undeniable that in some cases of disease it is clinically indispensable.

Writing of the nutritive value of alcohol in disease, Atwater says:

"What is wanted is a material which will not have to be digested, 17 can be easily absorbed, is readily oxidised, and will supply the requisite energy.

"I know of no other material which would seem to meet these requirements so naturally and so fully as alcohol. It does not require digestion, is absorbed by the stomach, and presumably by the intestine, with great ease. Outside of the body it is oxidised very readily, within the body it appears to be quickly burned, and it supplies a large amount of energy".

Professor Atwater, in 1899, made valuable experiments upon man in his respiration calorimeter (described on p. 10), in which 500 grammes of pure alcohol was given, disguised in a coffee mixture, and intended to replace a portion of the fats, starches, and sugars of ordinary diet. He found that "the alcohol was almost completely oxidised. The kinetic energy resulting from that oxidation agrees very closely with the potential energy of the same amount of alcohol as measured by its heat of combustion as determined by the bomb calorimeter, and the alcohol served to protect body protein and fat from oxidation".

It is, however, inferior to carbohydrates as a protector of body protein from consumption. In some cases it may even increase protein consumption, as, for example, when taken in such excess as to affect the nervous system and inhibit normal metabolism (Atwater).

In referring to the influence of alcohol upon metabolism Bauer says: "The increase of albumin suffers thereby no appreciable change; that of fat, on the other hand, is reduced by small quantities of alcohol, while by very large doses it is increased at any rate in animals. Alcohol also, in consequence of its fat-sparing action, behaves in the character of a food." The sugar which is contained in considerable quantity in sweet wines, liqueurs, etc., is an additional source of nourishment or of fat production. It is a matter of common observation that many heavy drinkers are stout. They usually indulge more freely in unsweetened liquors or malt liquors than in wines, however. Heavy drinkers are often heavy eaters, and may be as unable to control their appetite for food as for drink. This of course does not apply to cases of alcoholic gastritis, in which, temporarily at least, all desire for food may be in abeyance. In a general way, alcohol is believed to lessen tissue waste.

The consumption of alcohol is said to increase the quantity of oxygen inspired and lessen the carbonic acid exhaled.