The same nutritive essentials must be supplied whether the cost of the
diet be much or little. A moderately active man needs some 3,000 calories
per day whether his activity be playing golf or working on a farm; whether
his board bill be $3.00 a day or $3.00 a week. In both cases there must be
suitable kinds and amounts of protein-bearing food, of other "building
materials," and those substances which directly or indirectly affect the
smooth running of the body machinery; nevertheless, these two diets,
closely alike in nutritive value, may be very dissimilar in their
superficial appearance. For instance, all the nutritive requirements may
be met in a ration composed of three food materials, as milk, whole wheat
bread, and apples; on the other hand, by one composed of canvas-back duck,
truffles, lettuce, celery, cranberries, white bread and butter, cream,
coffee, and perhaps a dozen other items. We love all the various
sensations that come from the mingling in a meal of food hot and cold,
moist and dry, crisp and soft, sweet and sour, exhibiting the artistic
touch as well as the homelier virtues; it is the sacrifice of pleasure of
the esthetic sort that food economy and to some extent food conservation
entail.

The first step in food economy (aside from saving of waste) is to
emphasize the use of cereal foods. As much as one-fourth the food money
may be invested in grain products without nutritive disadvantage. But this
is not the last word on the subject, since cereal foods, while cheap,
differ among themselves in cost and somewhat in nutritive value. It is
possible to confine one's choice to some which contribute little besides
fuel to the diet, such as rice and white flour, or to include those which
are rich in other essentials, such as oatmeal. It is difficult to express
briefly this difference in foods in any concrete fashion, but recently a
method of grading or "scoring" foods has been introduced which may help to
make clearer the relationship between nutritive value and general economy.