36 ADVANCED PHYSIOLOGY 



sleep, by nervousness, by various diseases and by the action 

 of certain poisons and drugs, such as opium, chloral and 

 alcohol. It seems strange that men should consciously persist 

 in the use of some foods, and especially some drinks, which 

 inevitably bring about this increased katabolism in im- 

 portant organs; that they should continually expose them- 

 selves to weakening processes which the building up processes 

 can counterbalance with difficulty, if at all. 



Growth. The body is evidently a very active center into 

 which large amounts of material are constantly entering in 

 the form of food, drink and air, and from which, at the 

 same time, large amounts are constantly being eliminated. 

 Body substance is being constructed and destroyed at the 

 same time, and if these two processes are going on at the 

 same rate, the body neither increases nor diminishes either 

 in weight or efficiency. Such a condition is commonly 

 spoken of as one of metabolic equilibrium. 



If, on the other hand, the destructive processes take 

 place more rapidly than those of construction, the body will 

 lose in weight or efficiency, and if this condition of things 

 continues long enough, death must result. When the con- 

 structive processes in the body go on faster than the de- 

 structive or wearing away processes, the result is an in- 

 crease in weight or in efficiency. The growth of the body, 

 then, is the result of the excess of constructive changes over 

 destructive changes. 



Anabolism exceeds katabolism during childhood and ear 

 youth; but after adult life is reached, under ordin 

 circumstances the body maintains itself in metabolic eq 

 librium. This latter condition constitutes what is genera 

 spoken of as health, the maintenance of which should be a 

 matter of careful, serious attention as long as life lasts. 



ver 



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illy 



