The physiologic effects of alcohol and real food-stuffs are totally different. Fats, carbohydrates, and nitrogenous foods after mastication at once begin to be digested and assimilated, and to fulfil the true functions of a food by maintaining a natural temperature, pulse-rate, and tissue repair of the body, without any disturbance of its mental and physical functions and activities.
Alcohol, on the contrary, is absorbed from the stomach unaltered by the digestive processes; circulated in the blood in its original form, it at once interferes with the ordinary activity of the brain and other organs, and, by its anesthetic action, hampers the mental and physical activities and interferes with the processes of metabolism.
The Effects of Alcohol on the Digestive System and Metabolism.—The local action of alcoholic liquids is particularly destructive on an empty stomach; and when taken in strong solution, but it is also known that smaller doses, taken continuously, are liable to effect the digestive organs in a slower though similar way.
The injurious effects of alcohol are that it acts as a local irritant, producing dilatation of the blood-vessels of the stomach and subsequent gastritis; it leads to hyperacidity, by stimulating the secretion of hydrochloric acid; the tartrates and malates contained in wine are decomposed in the stomach, setting free organic acids, and thus producing acidity; the acetic acid and yeast in beer set up an acetic acid fermentation in the stomach-contents.
Whether taken alone or with food, the tendency of alcohol throughout is to lessen the churning movements of the stomach, and leads to atony of that organ, which in turn leads to dilatation of the stomach.
Alcohol appears to have a particularly deleterious effect on the digestion of women. This is explained by the fact that men lead a more active outdoor life, and consequently retain their appetite for food longer than women. For the same reason, they are able to work off the effects of drinking more easily and start afresh the assimilation of food. The indoor life led by women, their clothing, worn tight around the stomach, are added causes for lack of appetite. Catarrh of the stomach results; this is followed by insufficient food and an increased amount of stimulants. There follow nausea, irregular and insufficient nutrition, indigestion, and a faulty elaboration of the food.
By its action on the liver alcohol interferes with the amount and quantity of bile, and so inevitably leads to indigestion and constipation, and a similar interference with the action of the liver-cells and their chemical changes set up in many cases gouty conditions, accompanied by mental depression and irritability.
Diseases of the liver occur more frequently as the result of taking frequent small doses of alcohol, though never reaching the stage of intoxication, than as the result of indulging more freely, but at longer intervals.
The Effect of Alcohol on the Blood.—The blood is a mixture of corpuscles and a fluid known as the blood plasma. The corpuscles are of two kinds—red and white. The red blood-corpuscles are the oxygen carriers; they carry the oxygen to the tissues, where they readily give it up. They are constantly being destroyed by the liver and spleen, and are replaced by new ones, which come from the red marrow of bones. The white corpuscles are much fewer in number, but they play a most important part in protecting the body against disease. It is now about twenty years since Professor Metchnikoff, of the Pasteur Institute of Paris, announced to the world his discovery that the white corpuscles have the power of destroying the microbes to which so many diseases are due. These white blood-cells form the standing army or policemen of the body, and their duty is to attack, and, if possible, to destroy, any foreign matter, such as dust or disease germs.
The plasma of the blood contains various kinds of salts, and include sodium chlorid or common salt, the phosphates, and chlorids of calcium and potassium.