All About Coffee Part 37

says that the feeling of drowsiness after a full meal is a natural condition incidental to the proper conduct of digestion, and that to drive away this natural feeling with coffee must be an interference with the normal condition. However, if by so doing, we can increase our over-all efficiency without material harm to our digestive organs (and we can and do), the procedure has much in its favor both psychologically and dietetically.

The fact that coffee favors digestion without eventual disarrangement has been demonstrated above. On the subject of the relative agreement with the const.i.tution of foods of daily consumption, Dr. English[229]

said:

It is well known that there is no species of diet which invariably suits all const.i.tutions, nor will that which is palatable and salutary at one time be equally palatable and salutary at another time to the same individual. I think the most natural food provided for us is milk; yet I will engage to show twenty instances where milk disagrees more than coffee.

Further in this regard, Hutchinson[230] considers that ninety percent of the "dyspepsias" attributed to coffee are due to malnutrition, or to food simultaneously ingested, no disease known to the medical profession being directly attributable to it.

No one cognizant of the facts will contend that a cup of black coffee has any direct food value; but not so with the roasted bean. This has quite an appreciable content of protein and fat, both substances of high calorific value. The inhabitants of the Island of Groix eat the whole roasted coffee bean in considerable quant.i.ty, and seem to obtain considerable nourishment therefrom. Also, the Galla, a wandering tribe of Africa, make large use of food b.a.l.l.s, about the size of billiard b.a.l.l.s, consisting of pulverized coffee held in shape with fat. One ball is said to contain a day's ration; and, because of its food content and stimulating power, serves to sustain them on long marches of days'

duration.

When an infusion, or decoction, of roasted coffee is made, about 1.25 percent of the extracted matter is protein, it being accompanied by traces of dextrin and sugar. The same dearth of extraction of food materials occurs upon infusing coffee subst.i.tutes. This small amount can have but little dietetic significance. However, upon addition of sugar and of milk or cream, with their content of protein, fat, and lactose, the calorific value of the cup of coffee rises. Lusk and Gephart[231]

give the food value of an ordinary restaurant cup of coffee as 195.5 calories, and Locke[232] gives it as 156.

Mattei[233] found that 8 cc. of an infusion of roasted Mocha coffee of five-percent strength suppressed incipient polyneuritis in pigeons within a few hours' time. Their weight did not improve, but otherwise they were completely restored to health. However, in from four to six weeks after the apparent cure, the symptoms rapidly returned and the pigeons perished, with symptoms of paralysis and cerebral complications.

The temporary cure was probably due to caffein stimulation and secondary actions of the volatile const.i.tuents of coffee, which may be related to the vitamines; for it is not likely that the vitamines would withstand the heat of roasting. If B-vitamine does occur in roasted coffee, it is present only in traces.[234]

The inclusion of coffee in the average dietary is warranted because of its evident worth as an aid to digestion and for its a.s.similating power, thus earning its characterization as an "adjuvant food."

_Action of Coffee on Bacteria_

The employment of coffee as an aid to sanitation has been but little considered. Coffee, when freshly roasted and ground, is deodorant, antiseptic, and germicidal, probably due to the empyreumatic products developed during the process of roasting. An infusion of 0.5 percent inhibits the growth of many pathogenic organisms, and those of 10 percent kill anthrax bacteria in three hours, cholera spirilla in four hours, and many other bacteria, including those producing typhoid, in two to six days.[235]

The maintenance of a low rate of contraction of typhoid fever has often been attributed to drinking of coffee instead of water, the action of the coffee being partly due to the bactericidal effect of the caffeol and partly to the boiling of the water before infusion. The stimulating tendency of the caffein to sustain and to "tide over" those of low vitalities is also evidenced.

_Use of Coffee in Medicine_

Coffee has been employed in medicinal practise as a direct specific, as a preventive, and as an antidote. The _United States Dispensatory_[236]

summarizes the uses of caffein and coffee as follows:

Caffein is a valuable remedy in practical medicine as a cerebral and cardiac stimulant and as a diuretic. In undue _somnolence_, in _nervous headache_, in _narcotism_, also, at times when the exigencies of life require excessively prolonged wakefulness, caffein may be used as the most powerful agent known for producing wakefulness. In a series of experiments, J. Hughes Bennett found that within narrow limits there is a direct physiological antagonism between caffein and morphine. Coffee and caffein in narcotic poisoning are of value as a means of keeping the patient awake, and of stimulating the respiratory centres.

As a cardiac stimulant, caffein may be used in any form of heart failure; the indications for its use are those which call for the employment of digitalis. It is superior to digitalis in never disagreeing with the stomach, in having no distinctive c.u.mulative tendency, and in the promptness of its action. It is p.r.o.nouncedly inferior to digitalis in the power and certainty of its action, and in the permanence of its influence once a.s.serted. As a diuretic it is superior; it is very valuable in the treatment of _cardiac dropsies_, and is often useful in _chronic Bright's disease_ when there is no irritation of the kidneys.

On account of its tendency to produce wakefulness, it is usually better to ma.s.s the doses early in the day, at least six hours being left between the last dose and the ordinary time for sleep. From eight to fifteen grams (of caffein) may be given in the course of a day in severe cases. If tried, it would probably prove a useful drug in cases of _sudden collapse_ from various causes.

Good effects of coffee are recounted by Thompson.[237]

It removes the sensation of fatigue in the muscles, and increases their functional activity; it allays hunger to a limited extent; it strengthens the heart action; it acts as a diuretic, and increases the excretion of urea; it has a mildly sudorific influence; it counteracts nervous exhaustion and stimulates nerve centers. It is used sometimes as a nervine in cases of migraine, and there are many persons who can sustain prolonged mental fatigue and strain from anxiety and worry much better by the use of strong black coffee. In low delirium, or when the nervous system is overcome by the use of narcotics or by excessive hemorrhage, strong black coffee is serviceable to keep the patient from falling into the drowsiness which soon merges into coma. In such cases as much as half a pint of strong black coffee may be injected into the r.e.c.t.u.m.

Strong coffee with a little lemon juice or brandy is often useful in overcoming a malarial chill or a paroxysm of asthma. It is a useful temporary cardiac stimulant for children suffering collapse.

Dr. Restrepo,[238] of Medellin, Colombia, claims to have cured many cases of chronic malaria and related diseases with infusion of green coffee, after quinine had failed. Wallace[239] states that tincture of green coffee is a natural and efficacious specific for cholera, and that she knows of more than a thousand eases of cholera and diarrhea which have been treated with it without an isolated case of failure.

Landanabileo has been quoted as using raw coffee infusion in hepatic and nephritic diseases, venal and hepatic colics, and in diabetes.

In the Civil War, surgeons utilized coffee in allaying malarial fever and other maladies with which they had to contend, often under the most trying conditions, and with severely limited means of combating disease.[240] Its effect is to counteract the depressant action of low and miasmatic atmospheres, opening the secretions which they have checked. Travelers from the colder climes soon find that the fragrant cup of coffee is a corrective to derangements of the liver resulting from climatic conditions.[241]

Dr. Guilla.s.se, of the French Navy, in a paper on typhoid fever, says:

Coffee has given us unhoped for satisfaction, and after having dispensed it we find, to our great surprise, that its action is as prompt as it is decisive. No sooner have our patients taken a few tablespoonfuls of it, than their features become relaxed and they come to their senses. The next day the improvement is such that we are tempted to look upon coffee as a specific against typhoid fever. Under its influence the stupor is dispelled, and the patient arouses from the state of somnolency in which he has been since the invasion of the disease. Soon all the functions take their natural course, and he enters upon convalescence.[242]

Also it has been reported that in extreme cases of yellow fever, coffee has been used most effectively by many physicians as the main reliance after all other well known remedies have been administered and failed.

According to Lorand,[243] the use of coffee in gout is strictly prohibited by Umber and Schittenhelm; but he considered it a mistake absolutely to forbid coffee, as, when a person has good kidneys, the small amount of uric acid furnished by the caffein can readily be eliminated. A curious remedy for gout and rheumatism, the efficacy of which the writer scouts, is said to be[244]--a pint of hot, strong, black coffee, which must be perfectly pure, and seasoned with a teaspoonful of pure black pepper, thoroughly mixed before drinking, and the preparation taken just before going to bed. If this has any value, it is probably purely psychological in its function.

Several writers[245] attribute amblyopia and other affections of the sight to coffee and chicory, without giving much conclusive experimental data. Beer,[246] a Vienna oculist, however, held that the vapor from pure, hot, freshly-made coffee is beneficial to the eyes.

Coffee and caffein are physiologically antagonistic to the common narcotics, nicotine, morphine, opium, alcohol, etc., and are frequently used as antidotes for these poisons. Binz found that dogs that have been stupified with alcohol could be awakened with coffee. It may thus be prescribed for hard drinkers to counteract the baleful excitability produced by alcohol; in fact, many topers taper off after a long debauch with coffee containing small amounts of alcoholic beverages. Considering its ability to counteract the slow intoxication of tobacco, it may be inferred that coffee is indispensable for hard smokers.

In general, the medicinal value of coffee may be said to be directly attributable to its caffein content, although its antiseptic properties are dependent upon the volatile aromatic const.i.tuents. Its function is to raise and to sustain vitalities which have been lowered by disease or drugs. Although some of the cures attributed to it are probably purely traditional; still, it must be admitted, that by utilizing its stimulating qualities in many illnesses the patient may be carried past the danger point into convalescence.

_Physiological Action of "Caffetannic Acid_"

It has been demonstrated in chapter XVII that there is no definite compound "caffetannic acid," and that the heterogeneous material designated by this name does not possess the properties of tanning.

Further substantiation of this contention, and more evidence of the innocuous character of the tannin-like compounds in coffee, are contained in the testimony of Sollmann.[247] "Tannins precipitate proteins, gelatine, and connective tissue, and thus act as astringents, styptics, and antiseptics. The different tannins are not equivalent in these respects. Some (which are perhaps misnamed) such as those of coffee and ipecac, are practically non-precipitant.... On the whole, one may say that the small quant.i.ties of tannin ordinarily taken with the food and drink are not injurious, but that large quant.i.ties (excessive tea drinking) are certainly deleterious. The tannin of coffee is scarcely astringent, and, therefore, lacks this action," which is proven by the fact that it does not precipitate proteins.

"It has been claimed that 'caffetannic acid' injures the stomach walls, but there is no evidence that this is so."[248] Wiley,[249] in reporting some of his experiments, says: "Apparently the efforts to saddle the injurious effects of coffee-drinking upon caffetannic acid in any form in which it may exist in the coffee-extract are not supported by these recent data." The fact that tannins r.e.t.a.r.d intestinal peristalsis, whereas coffee promotes this digestive action, lends further proof to the non-existence of tannin in coffee. These statements by eminent authorities may be consolidated into the verity that there is no tannin, in the true sense of the term, in coffee; and that the const.i.tuents of the coffee brew which have been so designated are physiologically harmless.

_Physiological Action of Caffeol_

The evidence regarding the physiological action of caffeol is contradictory in many cases. J. Lehmann found in 1853, that the "empyreumatic oil of coffee, _caffeone_," is active; but more recent investigations have yielded results at variance with this. Hare and Marshall[250] believe that they proved it to be active. E.T.

Reichert,[251] however, found it inactive in dogs, excepting in so far that, when given intravenously, it mechanically interfered with the circulation. With it Binz[252] was able to produce in man only feeble nervous excitement, with restlessness and increase in the rate and depth of respirations.

The general effects, as summated by Sollmann[253] are, for _small doses_, pleasant stimulation; increased respiration; increased heart rate, but fall of blood pressure; muscular restlessness; insomnia; perspiration; congestion; for _large doses_, increased peristalsis and defecation; depression of respiration and heart; fall of blood pressure and temperature; paralytic phenomena. It is doubtful whether the quant.i.ties taken in the beverage cause any direct central stimulation.

Investigations have also been conducted with the various known const.i.tuents of this "coffee oil." Erdmann[254] found that in doses of between 0.5 and 0.6 gram per kilo of body weight, furane-alcohol kills a rabbit by respiratory paralysis; and that the symptoms of poisoning are a short primary excitement, salivation, diarrhea, respiratory depression, continuous fall of the body temperature, and death from collapse with respiratory failure. In man, doses of from 0.6 to 1 gram of furane-alcohol increased respiratory activity without producing other symptoms.

However, man is not as susceptible to these compounds as are the smaller animals. But even if their relative susceptibility be a.s.sumed to be the same, the lethal dose given the rabbit is equivalent to giving a 140-pound man one dose containing the furane-alcohol content of over 5,000 cups of coffee. Thus, in view of the very apparent minuteness of the quant.i.ty of this compound present in one cup of coffee, together with the fact that it is not c.u.mulative in its physiological action, the importance of its toxic properties becomes very inconsequential to even the most profuse and inveterate coffee drinkers.

Burmann[255] reported the volatile principle to have a reducing action on the hemoglobin; a depressing effect on the blood pressure; a depressant action on the central nervous system, disturbing the cardiac rhythm; and an action on the respiratory centers, causing dyspnea. The report of Sayre[256] regarding the minimum lethal dose of the concentrated combined active principles of coffee obtained from dry distillation is, for frogs, administered intraperitoneally and subcutaneously, 0.03 cubic centimeters per gram of body weight; for guinea pigs per stomach, 7.0 cc. per kilogram of body weight, and administered intravenously and intraperitoneally, about 1.0 cc. per kilogram.

This evidence regarding the physiological action of caffeol can not in any wise be construed to indicate a harmfulness of coffee. The percentage of these volatile substances in a cup of coffee infusion is so low as to be relatively negligible in its action. And, again, the caffein content of the brew, as will be seen, tends to counteract any possible desultory effects of the caffeol.

_General Physiological Action of Caffein_

More attention has been given to the study of the physiological action of caffein than to that of the other individual const.i.tuents of coffee.

Since certain of the effects of coffee drinking have been attributed to this alkaloid, a brief presentment of the pharmacology of caffein will be given as an exposition of the many statements made regarding it.

According to the _British Pharmaceutical Codex_[257]:

Caffein exerts three important actions: (1) on the central nervous system: (2) on muscles, including cardiac: and (3) on the kidney.

The action on the central nervous system is mainly on that part of the brain connected with psychical functions. It produces a condition of wakefulness and increased mental activity. The interpretation of sensory impressions is more perfect and correct, and thought becomes clearer and quicker. With larger doses of caffein the action extends from the psychical areas to the motor area and to the cord, and the patient becomes at first restless and noisy, and later may show convulsive movements.

Caffein facilitates the performance of all forms of physical work, and actually increases the total work which can be obtained from muscle. On the normal man, however, it is impossible to say how much of the action on the muscle is central and how much peripheral, but, as fatigue shows itself first by an action on the center, it is probable that the action of caffein in diminishing fatigue is mainly central. Caffein accelerates the pulse and slightly raises blood pressure. It has no action in any way resembling digitalis; by increasing the irritability of the cardiac muscle, its prolonged use rather tends to fatigue than to rest the heart.