514 THE HUMAN BODY 



to fat formation whenever the consumption of food happens to 

 exceed the immediate energy requirement. In the disease known 

 as exophthalmic goiter (Grave's Disease) the thyroid gland is ab- 

 normally active. The chief symptoms of the disease are those 

 that are associated with a greatly augmented metabolism. Suf- 

 ferers from the condition eat hugely and yet are emaciated. 

 Measurements of the daily energy turn-over show a heat produc- 

 tion that may be virtually double that of normal persons. 



Recently the interesting fact has been brought out that the 

 thyroid gland is subject to nervous stimulation by way of the 

 thoracico-lumbar autonomic system. Artificial Grave's Disease 

 has been produced in animals by causing persistent excitation of 

 those branches of the system that innervate the thyroid. Simi- 

 larly, the hormone adrenin, which stimulates tissues innervated 

 by the thoracico-lumbar autonomies, has been shown to excite 

 the thyroid to activity. The suggestion has been made that this 

 reaction is a part of the general emergency function of the Body. 

 Evidently a heightened metabolism, by increasing the outpouring 

 of energy, might be beneficial in time of stress. At present, how- 

 ever, this emergency action of the thyroid must be looked upon 

 as suggested rather than proved. 



The Treatment for Obesity is obviously to make the energy re- 

 quirement equal, or even exceed, the fuel intake. Vigorous mus- 

 cular exercise accompanied by strict dietary limitation may pro- 

 duce the desired result, but the good effects continue only so long 

 as the flesh-reducing measures are persisted in. Exercise and 

 dieting are both conducive to good appetite, therefore as soon as 

 the treatment is relaxed a return to the former condition is vir- 

 tually inevitable. Persistent semi-starvation, unaccompanied by 

 active exercise, is an efficient weight reducer. It should be re- 

 sorted to with intelligence, however, for undesirable impairment 

 of strength may follow its injudicious employment. A good rule 

 for those who wish to avoid gaining flesh is never to satisfy the 

 appetite wholly. On account of its specific dynamic action (p. 509) 

 protein is usually made the chief constituent of the diet in the 

 treatment of obesity. 



The administration of thyroid extract is a means of reducing 

 flesh by stimulating the oxidation processes of the Body. Since 

 the thyroid hormone has effects upon the nervous system (p. 202) 



