THERAPEUTIC ACTION OF FERMENTED MILK 41 



of lactic acid in the intestinal tract may exert a degree of anti-putre- 

 factive action. It should, however, be remembered that there are per- 

 sons with chronic inflammatory states of the digestive tract who 

 tolerate very badly acids of all sorts. These persons are unable to take 

 considerable quantities of fermented milk if the milk contains a high 

 percentage of lactic acid, the attempt to utilize such food being fol- 

 lowed by various unpleasant sensations and diarrhoea. The possible 

 anti-putrefactive influence of the presence of living lactic acid bacilli 

 in various parts of the digestive tract has already been discussed at 

 sufficient length and it has been pointed out that this factor again is 

 one whose value can not at present be accurately estimated. 



It must be plain from what has been said that the therapeutic use 

 of fermented milks rests at the present time rather more securely on 

 the clinical observations that have been made with it than on an ade- 

 quate scientific study of the influence exerted upon digestion and 

 nutrition and especially on the processes of putrefaction. To obtain 

 the necessary scientific data will require elaborate and very laborious 

 experiments covering long periods of time. With the aid of such 

 experiments I have no doubt that the usefulness of soured milks in 

 health and in disease will be definitely and discriminatingly estab- 

 lished. The limitations of utility will become equally plain, and I 

 predict that they will prove to be many. The importance of this sub- 

 ject for the welfare of people at large not only in respect to immediate 

 physical comfort and efficiency but as regards the prolongation of life, 

 would, in my opinion, amply justify a very considerable expenditure of 

 money to acquire this knowledge. 



It can not be regarded as surprising that the enthusiasm which 

 has been aroused partly through the public exploitation of various 

 kinds of fermented milk in the treatment of disease and partly by the 

 undoubted successes of the treatment should have led to various abuses. 

 One of the most important things to understand in reference to the 

 use of fermented milk is that it should be employed in most instances 

 as a substitute for other forms of food rather than as an addition to 

 the usual dietary. Especially is it necessary to bear this in mind in 

 the case of chronic disorders associated with an increase in putrefac- 

 tion. The addition of a considerable amount of fermented milk to the 

 habitual dietaiy has often been practised with disastrous results, and 

 I do not doubt that this practise is still widely extended. Such bad 

 results might be predicted, for since all fermented milks contain a 

 large proportion of protein material capable of undergoing putrefac- 

 tion and since this putrefaction is not checked, in any specific way, 

 through the agency of the fermented milk itself, a great increase of 

 putrefactive decomposition may follow the injudicious excessive use 



