DIETETICS 631 



an enema. After the enema the quantity of hydrochloric acid secreted 

 increased in about the same proportion as the quantity of juice, but the 

 pepsin was diminished, reaching a minimum after three-quarters to 

 one and a quarter hours. The increase in the total quantity of the 

 juice and in the acid over-compensated the moderate diminution in the 

 digestive power, so that the net result was beneficial (Pekelharing). 

 But it must be remembered that strong alcoholic beverages, when mixed 

 with the gastric juice, and therefore when taken by the mouth, retard 

 the proteolytic action, so that any favourable effect on the secretion of 

 the juice may easily be lost in the subsequent digestion, unless the 

 alcohol is dilute (Chittenden and Mendel) . The action of alcohol intro- 

 duced into the rectum on the gastric secretion is both reflex and direct. 



(5) Alcohol is of no use for healthy men. 



(6) Alcohol in strictly moderate doses,* properly diluted and especi- 

 ally when taken with the food, is not harmful to healthy men, living 

 and working under ordinary conditions. 



(7) Modern experience goes to show that in severe and continuous 

 exertion, coupled with exposure to all weathers, as in exploring expedi- 

 tions, alcohol is injurious, and it is well known that it must be avoided 

 in mountain climbing. 



The drastic restrictions placed upon the use of alcoholic beverages in 

 most of the belligerent countries during the present war, although 

 adopted for economic as well as for physiological reasons, do not favour 

 the view that the efficiency of the fighting man, or of the man who works 

 at high pressure to equip and supply him, is increased by alcohol. But 

 it would be quite erroneous to conclude that because alcohol, as such, 

 may not at all improve the working or staying power of men accustomed 

 to use it moderately, it can be suddenly and completely prohibited 

 without detriment to their work. The factor of habit and its influence 

 on efficiency has been far too little considered in connection with this 

 question. The man who craves his wonted glass of beer, even if he 

 does not resent its withdrawal, will almost certainly suffer in efficiency 

 for a while, although the beer in itself may not have aided him in his 

 work. 



Alcohol in small doses, when given by the stomach or (in animals) 

 injected into the blood, causes stimulation of the respiratory centre and 

 increase in the pulmonary ventilation. In man, this increase usually 

 amounts to 8 to 15 per cent., but is occasionally much greater. But the 

 limit which separates the favourable action of the small dose from the 

 hurtful action of the large, is easily overstepped. When this is done, 

 and the dose is continually increased, the activity of the respiratory 

 centre is first diminished and finally abolished. In dogs, for instance, 

 after the injection of considerable quantities of alcohol into the stomach, 

 death takes place from respiratory failure, and the breathing stops 

 while the heart is still unweakened (Fig. 85, p. 191). This is the final 

 outcome of a progressive impairment in the activity of the centre, of 

 which the slow and heavy breathing of the drunken man represents an 

 earlier stage. 



Tea, coffee, and cocoa are more suitable stimulants for healthy 

 persons, because they are less dangerous than alcohol, and they 

 leave no unpleasant effects behind them. But it should be remem- 



* Not more than i oz. of absolute alcohol, corresponding to about 4 oz. of 

 whisky, or 2 to 3 wineglasses of sherry or port, or a pint of claret, or a couple 

 of pints of light beer in 24 hours. 



