40 THE POPULAR SCIENCE MONTHLY 



with habitual excess in putrefaction. In view of this fact it is clear 

 that in experiments designed to determine the influence of fermented 

 milks upon the intensity of putrefaction it is essential to take accurate 

 cognizance of the quantity of protein ingested. It is easy to under- 

 stand that if a patient has been in the habit of eating for his midday 

 meal an abundance of protein food and decides under advice to take 

 a fermented milk for his lunch in place of the more elaborate meal, 

 the mere reduction in protein will suffice to reduce putrefaction. So 

 it is clear that a decrease in putrefaction can be effected through a 

 variety of dietaries which have in common the fact that they contain 

 a smaller amount of protein material than the patient has been in the 

 habit of eating. Whole milk and various fermented milks are thus 

 capable of influencing putrefaction in such a way that we may readily 

 fall into the error of exaggerating their influence upon putrefactive 

 decomposition in the intestine. Hence it is evident that the only fair 

 test of the value of a fermented milk in respect to its influence on 

 putrefaction is to compare it with the effects of other articles of diet 

 containing exactly the same amount of protein material. Such care- 

 ful comparisons have not, I believe, been made up to the present time. 

 In the future they will doubtless be made and will enable us to form 

 quite definite judgments as to the relative effectiveness of different 

 kinds of fermented milks upon intestinal putrefaction. At present I 

 should hesitate to say that one kind of fermented milk is more effective 

 than another in bringing about a reduction in intestinal putrefaction. 

 "We may regard it as well established that a diet in which milk 

 takes the place of other kinds of food is very apt to be followed by a 

 reduction in the intensity of putrefactive decomposition in the intes- 

 tine. There are, however, clinical indications that the use of fer- 

 mented milks does possess real advantages over the use of whole milk 

 at least in some disorders of digestion. Although the exact character 

 of these advantages is not yet firmly established, they seem to be none 

 the less real. From what has already been said in this paper on the 

 criteria of judgment of the action of fermented milks, it is evident 

 that the clinical advantages which have been observed may be attrib- 

 utable to several different peculiarities possessed by fermented milks in 

 general. One of these is the favorable mechanical influence on the 

 minute subdivision of the casein, which prevents the undesirable effects 

 associated with the presence of large clots of casein which are not 

 easily disposed of in persons with weak digestion. The exact conse- 

 quences of this advantageous mechanical state of the milk food can not 

 now be appraised. A second point which has already been mentioned 

 is the formation of lactic acid. Here again the precise extent of the 

 favorable influence can not be measured; but on the other hand it can 

 not be denied that in at least some disorders of digestion the presence 



