


AVAILABILITY AND FUEL VALUE OF FOOD MATERIALS. 8I 
In examining the 185 studies they are first divided into 
classes according to the occupation of the persons studied. 
The majority of the studies were of families of day laborers, 
mechanics, farmers, professional men, etc. There were also a 
number of dietaries of boarding houses and of college students’ 
clubs, and a few of individuals or special groups of persons, 
especially of athletes, as rowing crews, foot-ball teams and bicy- 
cle racers. They were made in different parts of the United 
States, from Maine to California. All belong to the nutrition 
investigations which have been carried out for some years past 
under the auspices of the U. S. Department of Agriculture by 
investigators connected with a considerable number of educa- 
tional and scientific institutions.* 
The food materials used in each dietary were divided into 
the following groups: 
Beef and veal, Corn meal, rye and buckwheat flour, 
Mutton and Jamb, Oat meal, rice and wheat preparations, 
Pork, Wheat flour, bread, crackers; pastry, etc., 
Poultry, Starch, 
Fish, Sugar, 
Eggs, Dried legumes, 
Butter, ~ Potatoes and sweet potatoes, 
Cheese, Other vegetables, 
‘Milk and cream, eeu its: 
The published statistics of each study show the total weights 
of the nutrients—protein, fats and carbohydrates—in each food 
material in each dietary. From these data the total weights of 
nutrients in each group of food materials were found. From 
these figures for total weights of protein, fats and carbohy- 
-drates in the different groups—beef and veal, dairy products, 
cereals, vegetables, etc., there were computed the percentages 
which these weights formed of the total amount of protein, 
fats and carbohydrates in the diet. In a similar manner the 
statistics of the total food materials in each dietary were used 
for calculating the percentages of the whole occurring in each 
group of materials. 
Having thus found the proportion of total foods and the 
different nutrients that were furnished by the different kinds 
or groups of food materials in each dietary, the averages 

* The original data are to be found in the Nutrition publications of the Office of 
Experiment Stations and in the Reports of this Station. 
