356 HUMAN PHYSIOLOGY 



the presence of the intestinal bacteria but, on the other 

 hand, in the majority of cases they are not known to 

 harm him. Mischief may be done either by a general 

 excess of bacterial activity or by the substitution of 

 hurtful for innocuous forms. 



Measures against Auto -intoxication. We have sug- 

 gested that this undesirable condition may result when 

 the digestion has been retarded as a result of psychic 

 factors. It may equally well follow disturbances set 

 up in other ways. Overeating is probably a frequent 

 cause. If the capacity of the canal to absorb all the 

 food presented is overtaxed there will be residues to be 

 decomposed. It is fortunate that in many cases of 

 overindulgence a mild diarrhea is the most obvious 

 sequel. Auto-intoxication is minimized by the vigorous 

 sweeping out of the threatening material. A cathartic 

 may insure the same protection, but should not be 

 resorted to at all frequently. 



It might be supposed that overeating would lead 

 automatically to loss of appetite and so correct itself. 

 But we cannot rely upon any such adjustment. A 

 slightly excessive consumption of food may have no 

 evident injurious effect for long periods of time, yet the 

 ultimate result may be the shortening of active life 

 through the early development of arteriosclerosis. 

 It almost seems as though the subtle changes induced 

 by such a small dietetic error were more serious than 

 those likely to follow a more gross transgression. 



Temperance in eating is doubtless the chief practice 

 to be recommended as a safeguard against auto-intoxica- 

 tion and its evils. Temperance in drinking might be 

 mentioned at the same time, for the moderate drinker 

 is disposed to overeat and alcohol itself is a common 

 cause of arteriosclerosis. It is more important to 

 restrict the protein food than the other kinds, for the 

 definitely poisonous compounds . entering the blood 

 from the colon are believed to be nitrogenous. Modera- 

 tion in meat-eating is to be urged, but the reason, it 



