The Washington times., 1894-03-20
VALUES OF VARIOUS FOODS
Prof. c. D. Woods on the Science Of
Nutrition.
MAKES HEAT AND ENERGY
Tables Showing the Amount Of Food Neces-
sary to Properly Nourish Man-Vege-
table and Animal Foods-Cost Of Living
in Various Countries.

Woods, OF the Storrs Agricultural Experiment
Station, in the report of the New Jersey State
Board of Agriculture, is simple matter. but
are utilized in maintenance of life are far
from simple. Our bodies and the food we eat
are composed of the same chemical elements,
and the compounds Of these elements in food
are quite similar to those which make up the
body. The way of finding out how
food is used consists in the comparison of tho
income with the outgo of the body The body
creates nothing for itself, either of material
or energy. All must come to it from without.
The science of nutrition, as it is un-
derstood to-day, is matter of definite guam
titles of income and expenditure, measured
in terms of chemical compounds, and of heat
and mechanical energy.
The chief two uses of food of animals are:
First to form the materials OF the body and
make up its wastes; and second to yield energy
in the form of heat to keep the body warm,
and muscular and other power for the work
it has to do. In forming the tissues and
fluids of the body the food serves for build
luS anu lcpdli LII ScINt5
as fuel
The different nutrients of food act In diff
ferent ways in fulfilling these purposes. The
principal tissue formers are the protein COM
pounds. These form the framework OF the
body. They build up and repair the nitro
genous materials, as the muscle and bone,
and supply the albuminoids of blood, milk,
and other fluids. The chief fuel ingredients
of food are the carbohydrates and fats. These
are either consumed in the body or are stored
as fat to be used as occasion demands. In
being used as fuel tie nutrients of the
food tend to protect each other and the ma
terials of the body from being consumed.
Heat and muscular power, like mechanical
power, light, and electricity, are forms of
energy. The energy is latent in the food and
is developed as the food is consumed in the
body. The value of food for fuel is
expressed in terms of potential energy. The
quantities of potential energy in food are de-
termined by experiments with an apparatus
called calorimeter. The unity commonly
used is the calorie. the amount of heat which
would raise the temperature Of a kilogram of
water one degree centigrade Cor pound of
water four degrees Fahrenheit.)
Taking ordinary food materials as they
come, the following general estimate has been
made for the average amount of energy in
one-hundredth Of pound of each of the
classes OF nutriments:
In 00l pound protein SO calories
In 00i pound fats. .i2 calories
In 00l pound carbohydrates ........Is6 calories
Printed tables were distributed showing
proportions of each of the three constituents
in one pound of various kinds OF foods. The
composition of fcooked canned corned beefis Of
considerable Importance. Its high content both
of proteins and fats is due to the loss of water
that comes from the process of cooking and
preparation. 1t furnishes pound for pound
more protein than the other specimens of
beef and nearly equals the highest of them in
its potential energy From personal obser-
vation also of the methods of its manufacture.
/ can recommend it as one of the most excel
lent and economical OF foods.
The vegetable foods differ very materially
from the animal foods in both composition
and digestibility. For the most part they are
not as completely digested, and more energy
is used up In the assimilation of the digested
portions than is the case with animal foods.
So that in general given weight of protein
or fat from vegetable food will not furnish
as much material for the use of the body as
the same weight from other sources.
Beans are very rich in protein, and on this
account are very valuable food. Cornmeal
differs from wheat flour in having more fat
and less protein and carbohydrates. The
total energy food value) OF these two foods
is nearly the same.
In being consumed in the body to furnish
heat and muscular energy the nutrients re-
place one another n proportion to their
potential energy. 1t has been esti-
mated that man, to keep his body we'll
nourished, requires about OBS pound Of
protein and sufficient quantities of fat and
carbohydrates to furnish, together with that
of the protein. about $3.50 calories of poten-
tial energy. He would also need a certain
amount of mineral matters and water. Suffi-
cient nutrients to furnish that amount OF
potential energy would be contained in the
following food materials. which would there
fore suffice for days nourishment.
FOOD MATERIALS WHICH WOULD FURNISH NUTRT-
ENTs FOR ONE DAY FOR A MAN AT MODERATE