140 INFLUENCE OF FOOD PRESERVATIVES ON HEALTH. 



fore period, as seen in the fact that the percentage of phosphoric acid 

 absorbed is a little less during the after period than it is during the 

 preservative period, but still somewhat greater than daring the fore 

 period. The effect of the preservative on the fat is seen in the sum- 

 mary of the data, showing that 5.1 per cent of all the fat in the food 

 appears in the feces during the fore period, 4.2 per cent during the 

 preservative period, and 3.7 per cent during the after period. The 

 tendency in this case is the same as regards the phosphoric acid, namely, 

 to increase slightly the absorption of the fat during the preservative 

 period. In regard to the calories it is seen that there is little difference 

 between the fore period and the preservative period in the percentage 

 of calories in the food eliminated in the feces. During the after period, 

 however, there is a tendency to increase the absorption of calories, 

 only 4.1 per cent of the total amount in the food appearing in the 

 feces in the after period, as against 4.2 per cent during the preservative 

 period and 4.2 per cent during the fore period. 



The summary shows a slightly deranging effect upon the appetite 

 during the preservative period, as indicated by the smaller quantities 

 of food consumed. Of course an effort has been made to have practi- 

 cally the same quantities of food consumed during all periods, but it is 

 found impracticable to control absolutely the influence of the appetite, 

 and occasionally when the appetite fails a portion of the food is 

 weighed back and deducted from the portion issued. It is deemed 

 better to introduce this disturbance^into the data than to risk the more 

 pronounced effect of deranging the digestion still further by insisting 

 upon the consumption of the full ration of food when the appetite 

 rebels. In so far as the calories are concerned, it is seen that a con- 

 siderably less quantity of food is used per day during the preservative 

 period, the average calories for this period being 2,851 as against 

 3,075 in the fore period. The. appetite does not recover its full vigor 

 during the after period, the quantity of food consumed being practi- 

 cally the same, in so far as calories are concerned, as that eaten dur- 

 ing the preservative period. 



Considering as a whole the summary of Series III, it appears that 

 the administration of the preservative slightly affects the appetite of 

 the class, decreases the percentage of nitrogen absorbed, increases the 

 percentages of phosphoric acid and fat absorbed, and diminishes the 

 percentage of the calories absorbed. In this series the individual data 

 are often contradictory, and the interpretation of the data must be 

 influenced to a greater or less extent by peculiarities in the individuals 

 themselves. It seems difficult, however, to avoid the conclusion in 

 this case that the administration of the preservative in the manner 

 described and in the quantities indicated produces a slightly depressing 

 or injurious effect upon the processes of digestion. 



