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ON DIETETICS. 
Both theory and practice justify the statement, that the 
nutritive functions are under great, almost entire control, 
and that, under a rigid system of dieting, the results may be 
predicated with tolerable certainty. 
Food, like medicine, is capable of producing certain effects 
allied to the phenomena of disease. 
When the quantity assimilated corresponds to the waste 
of the tissue, we recognise the legitimate end of the nutritive 
function—reparation. 
When the quantity is excessive, if assimilation continue, 
the consequence is plethora. 
If assimilation be arrested, various forms of disturbance 
follow the irritant effects of the undigested mass. 
When the quantity is defective, the waste of texture is 
imperfectly supplied, and the result is emaciation. 
When the quality is deteriorated, in consequence of the 
admixture of non-alimentary matters, various actions result, 
corresponding to the properties of the foreign bodies, varying, 
from simple defective nutrition, through various degrees of 
irritation, to absolute poisoning. 
Therapeutic Action of Food. 
After what has been stated upon the physiological effects 
of food, it is sufficiently obvious that those effects can be pro¬ 
perly arranged in three groups, similar to those into which 
we have divided medicinal agents ; we have, indeed, in the 
agents of an ordinary dietary, means of producing excess, 
defect, and, even perversion, and consequently to a certain 
extent of remedying those diseased conditions when they 
occur in the organism; accepting as an axiom the statement 
that the objects of medicinal and dietetic treatment are 
identical, whatever is sought in the employment of medicine 
shall also be sought in the arrangement of the diet, how 
far this rule is observed we shall have frequent opportunities 
of showing during our discussion of various portions of the 
subject. 
Dietetics for Acute Diseases. 
The necessity for supplying a certain quantity of nutriment 
to the system does not cease upon the occurrence of disease, 
although it may be considerably modified, at least for a time. 
This circumstance renders it advisable to decide upon the 
precise object desired, before any system of dieting be 
arranged. The simple inquiry, what is necessary ? in refer- 
