FACTORS INFLUENCING INTESTINAL BACTERIA 237 
Unfortunately a qualitative study of the bacteria in the feces was not 
made during this study and to secure such information it 1s necessary 
to consult the work of others. Herter and his colleagues, the work of 
whom has been summarized by Herter (1907), have given information 
to show that a protein diet induces the proteolytic group. Rettger and 
his colleagues have studied the effect of carbohydrate feeding. The 
experiments were made with laboratory animals and man. Hull and 
Rettger (1915) studied the effect of milk and carbohydrate feeding. 
They found that lactose when taken by adults along with their usual 
food, caused a shift in the flora to the acidophilli group of bacteria. 
B. acidophilus and B. bifidus appeared with the former more abundant. 
The most practical diet, however, to produce these results was a com- 
bination of milk and lactose. B. bulgaricus was not found which is in 
accord with the work of others. 
Fasting has a decided effect on intestinal bacteria. As quoted above 
Blatherwick and Hawk (1914), during fasting, noticed a decided reduc- 
tion in the amount of bacterial nitrogen and bacterial substance. Sisson 
(1917) has found that, after periods of starvation, there are definite 
changes in the number of bacteria in contrast to the usually vigorous 
erowth. No change in the kind of organism after starvation was noted. 
The greatest decrease in the number of bacteria was noticed in the duo- 
denum. Sisson regards the condition produced by starvation as one of 
relative amicrobism. 
In this connection the influence of copious water drinking on fecal 
bacteria should be mentioned. Fowler and Hawk (1910) noticed a 
decrease in the total nitrogen appearing as bacterial nitrogen. The 
following weights of fecal bacteria were excreted per day during the 
periods mentioned: 
Preliminary... 0.0. ....000 eee eee 5.327 gms. per day 
Water period ..........-.---00-- 4.579 gms. per day 
Final period... ..... .....--0--- 3.280 gms. per day 
Hattrem and Hawk (1911) by means of copious water drinking 
obtained a decrease in putrefaction and stated that it was probably due 
to a decrease in the activities of indol-producing bacteria following 
accelerated absorption of products of protein digestion. Copious water 
drinking (1000 c.c.) caused a decrease of indican in the urine which 
was accompanied by an increase of ethereal sulphates. The drinking of 
distilled and softened waters were found by Sherwin and Hawk (1914) 
to cause a decrease in intestinal putrefaction as measured by urinary 
indican. 
