
EXPERIMENTS ON DIGESTION OF FOOD BY MEN. 163 
EXPERIMENTS ON THE DIGESTION OF FOOD 
BY MEN. 


REPORTED BY W. O. ATWATER. 
The Reports of this Station have contained accounts from 
time to time of digestion experiments with animals. The object 
of the present article is to describe the methods and results of 
experiments upon the digestion of different food materials by 
healthy men. As investigations of this particular kind are new 
in the United States a brief account of the purpose and plan of 
the experiments may be in place.* 
The value of food for nutriment depends not only upon the 
amount of nutrients it contains, but also upon how much the 
body can digest and use for its support. 
The question of the digestibility of food is very complex, and 
the current ideas regarding it are more or less indefinite and 
confused. One source of this confusion is the fact that what 
people commonly call the digestibility of food includes several 
very different things; some of which, as the ease with which a 
given food material is digested, the time required for the 
process, the influence of different substances and conditions 
upon digestion, and the effects upon comfort and health, are so 
dependent upon individual peculiarities of different persons, 
and so difficult of measurement, as to make the laying down of 
hard and fast rules impossible. Why it is, for instance, that 
some persons are made seriously ill by so wholesome a material 
as milk, and others find that certain kinds of meats or vegeta- 
bles or sweetineats ‘‘ do not agree with them,”’ it is difficult to 
explain. Late investigation, however, suggests the possibility 
that the ferments in the digestive canal or elsewhere may, with 
some people, cause particular compounds to be changed into 
injurious or even poisonous forms so that sometimes it may be 
literally true that ‘‘ One man’s meat is another man’s poison.’’ 
” * Detailed statements regarding the methods and results of inquiry in this direction 
may be found in Bulletin No. 21 of the Office of Experiment Stations of the United 
States Department of Agriculture on “ Methods and Results of Investigations on the 
Chemistry and Economy of Food.” — 
