NATURE AND DESTINATION OF FOOD. Ill 



67. 'The absolute quantity of Food required for the maintenance of the Hu- 

 man body in health, varies so much with the age, sex, constitution, and habits 

 of the individual, and with the circumstances in which he may be placed, that 

 it would be absurd to attempt to fix any standard which should apply to 

 eveuy particular case. The appetite is the only sure guide for the supply of 

 the wants of each ; but its indications must not be misinterpreted. To eat 

 ir/icn we are hungry, is an evidently natural disposition ; but to eat as long 

 as we are hungry, may not always be prudent. Since the feeling of hunger 

 does not depend so much upon the state of fulness or emptiness of the 

 stomach, as upon the condition of the general system, it appears evident that 

 the ingestion of food cannot at once produce the effect of dissipating it, 

 though it will do so after a short time ; so that, if we eat with undue rapidity, 

 we may continue swallowing food long after we have taken as much as will 

 really be required for the wants of the system ; and every superfluous particle 

 is not merely useless but injurious. Hence, besides its other important ends, 

 the process of thorough mastication is important, as prolonging the meal, 

 and thus giving time to the system to be made acquainted (as it were) that 

 the supply of its wants is in progress ; so that its demands may be abated 

 in due time to prevent the ingestion of more than is required. It is very 

 justly remarked by Dr. Beaumont, that the cessation of this demand, rather 

 than the positive sense of safety, is the proper guide. "There appears to 

 be a sense of perfect intelligence conveyed to the encephalic centre, which, 

 in health, invariably dictates what quantity of aliment (responding to the 

 sense of hunger and its due satisfaction) is naturally required for the pur- 

 poses of life; and which, if noticed and properly attended to, would prove 

 the most salutary monitor of health, and effectual preventive of disease. It 

 is not the sense of satiety, for this is beyond the point of healthful indul- 

 gence, and is Nature's earliest indication of an abuse and overburden of her 

 powers to replenish the system. It occurs immediately previous to this ; and 

 may be known by the pleasurable sensations of perfect satisfaction, ease, 

 and quiescence of body and mind. It is when the stomach says, enough; 

 and it is distinguished from satiety by the difference of sensations, the 

 latter saying too much." Every medical man is well aware how generally 

 this rule is transgressed ; some persons making a regular practice of eating 

 to repletion ; and others paying far too little attention to the preliminary 

 operations, and thus ingesting more than is good for them, even though they 

 may actually leave off with an appetite. 



68. Although no universal law can be laid down for individuals, it is a 

 matter of much practical importance to be able to form a correct average 

 estimate. But even this is given somewhat differently by different observers. 

 Dr. Daltou, for instance, 1 states that the entire quantity of food required 

 every 24 hours by a man in full health and taking free exercise is, of meat 

 16 oz. av., bread 19 oz., fat 3? oz., and of water 52 fl. oz., that is, about 

 2j Ibs. of solid food, and rather more than 3 pints of fluid. Vieroidt 2 con- 

 siders the adult to be well nourished if, with moderate exercise, he receives 

 daily about 4 oz. of dry albumen, 3 oz. of fat, 11 > oz. of some starchy sub- 

 stance, and about 1 oz. of salts, which gives a proportion of one part of 



tinners of long experience, characterizes the present generation as compared with 

 the preceding. But whilst there is a diminished capability of bearing large blood- 

 lettings, violent purgation, etc., there is at the same time such an increased tendency 

 to a lavorable termination in many of those diseases for which they were formerly 

 accounted necessary, as should remove all regret at this change of constitution. On. 

 the question of "Vegetarianism," the author may refer to his articles on that sub- 

 ject in the Brit, and For. Med.-Chir. Kev., vol. vi, pp. 76 and 399. 



1 Physiology, 1801, p. U7. 2 Grundriss d. Phys., 1860, p. 192. 



