

8 

STUDIES OF DIETARIES. 125 
professional man’s family. ‘The main results of these inquir- 
ies, including all the data used in the computations, are given 
in the following statements and tables. The dietary studies in 
the State Hospital for the Insane are, however, treated briefly 
by themselves in the succeeding article. 
Methods.—Vhe methods of dietary study followed by the Station have been 
fully described in former Reports.* The general plan includes (1) determina- 
tions of the amounts and costs of all the different food materials on hand at the 
beginning of, purchased during, and remaining on hand at the end of the 
investigations; (2) when practicable, the collection and analysis of kitchen and 
table waste; (3) a record of the weight, age, sex, and occupation of the differ- 
ent members of the group under observation, and the number of meals taken 
by each. From these data, and those for the composition of food materials, as 
determined by analyses of samples of the materials actually used or as assumed 
from averages of analyses of similar materials, the total amounts of protein, 
fats, and carbohydrates in the dietary and the amounts consumed per man per 
day are computed. 
In carrying out the studies here reported the usual methods were followed as 
far as possible. In the two dietary studies carried out in the Hospital for the 
Insane (Nos. 253 and 254), the methods were necessarily somewhat modified. 
For instance, the various kitchens of the Hospital are served each day with raw 
materials from the general supply. In making a study in two of the buildings, 
therefore, it was not practicable to take an inventory of the materials on hand 
at the beginning and end of the study. ‘The usual data concerning the kinds 
and amounts of foods consumed were obtained by keeping record of the weight 
of all the food materials used in the kitchen in the preparation of each meal. 
Weights were also taken of all materials sent from the kitchen to the dining 
room, and returned from the dining room to the kitchen. Considerable of the 
- data thus obtained were, therefore, for the cooked foods actually eaten. In 
estimating the amounts of nutrients contained in these materials the composi- 
tion was calculated from the total weight of the cooked product and the weights 
and composition of the raw ingredients used in preparing them. : 
In the studies of three individual college students (Nos. 318, 319, and 320), 
there were also some modifications of the usual methods. ‘The data concerning 
the kinds and amounts of food actually consumed were obtained by the students, 
each of whom weighed, at the table, all of the food that was served to him for 
each meal, and recorded the weight together with such information as he could 
give concerning the character of the food, the method of preparing it, etc. In 
these studies the large majority of the statistics are, therefore, for cooked food 
materials as prepared for the table. It was not possible to make analyses of 
samples of the foods eaten nor to get data by which to calculate the composi- 
tion of the cooked foods from the weights and composition of their ingredients. 
“The-percentages of nutrients in the foods were assumed to be the same as in 
similar cooked food materials, the composition of which had been already 
determined or computed. But it is obvious that the composition of such 
materials will:-vary widely, according to the recipes used in their preparation. 
The results of these studies, therefore, may be considered less reliable than the 
* See Reports of this Station for 1891-96. o 
