Iowa state bystander. [volume] (Des Moines, Iowa) 1894-1916, 1914-10-23
(copvriSht. lslA BY A S. Gray)
PROTEIN FOOD.

PROTEIN FOOD.
We have noted that the average
man. kept absolutely motonless In
bed and fasting. develops 1.S25 calo-
ries . day. an amount OF energy equiv.
alent to lifting one ton (2.oO0 pounds)
more than $500 feet and that 70 this
must be added the energy expended IN
every additional motion, even to the
additional heart beats resulting from
mental excitement or any other form
Of muscular action. This implies
combustion OF tissue fuel and, OF
course, wherever there IL combustion,
unless 1t be Of pure carbon. there
must be waste or ash.
Among our main food materials the
proteins are characterized by contain
ing nitrogen in wonderfully complex
molecule that passes through q bewil-
dering series of metabolic changes IN
our bodies and finally, after having
completed the cycle, is expelled from
the body chiefly in the urine. but to
smaller extent in the feces and
sweat.
Psychologists take these facts as
basis from which to figure the food
requirements of our bodies. and when
they speak of the nitrogen balance, or
the carbon balance, they refer to that
amount Of nitrogen or carbon intake
that il exactly balanced by the
amounts OF nitrogen or carbon ex.
creted from the body. Nitrogen equi-
librium, then, il that state OF body
in which the nitrogen intake 10 ex.
actly balanced by the nitrogen COM
pounds expelled. II the balance is
even, then the body lie. receiving in the
food as much protein nitrogen as 1t Is
metabolizing and eliminating in the
excreta. II there is plus balance In
favor of the food 1t is evident that the
body is laying on or storing protein.
while II the balance Is minus, that 10.
II the total nitrogen excreted exceeds
the nitrogen protein taken IN the food.
the body must be losing protein.
Obviously, anything that win tend
to disturb the normal appetite must
upset this delicate balance, and there
In lies the disadvantage and the grave
danger In using dietetic whips in the
shape of condiments, sauces, cock.
tails and all highly favored non-nutri.
tious substances. 1t Is important to
bear In mind the fact that nitrogen or
protein equilibrium may easily be e.
tablished on different levels. For in.
stance. one may be In nitrogen eQui.
lbrium on one ounce of protein and
may increase 1t to two or three ounces
and still be in equilibrium. Just as you
can burn in your furnace three buck.
etc Of coal day or ten. Experience
teaches that the extra protein is me-
tabolized in the, body and equilibrium
is established on = higher level 80 that
there is no accumulation, but the Or
gans must work harder to expel the
additional ash. Experimentally 1t has
been found that there is q certain low
limit Of protein which Just sufiices to
maintain nitrogen balance. and be-
tween this level and the maximum ca.
pacity Of the body to digest and ab.
sorb protein food the nitrogen eQui.
librium may be maintained upon any
given amount OF protein. The invest.
cations of Chittenden and others in
this field seem to show that nitrogen
equilibrium may easily be maintained
on a plane vastly lower than that gen.
orally prevailing, and to lower the
protein allowance approximately to
this minimum undoubtedly would be
of great benefit to the average indi-
vldual in many ways, especially dur
ing hot weather. g. /. -.
Nitrogen Is eliminated from the
body as urea, creatinine and uric acid.
Urea is the most important of the nj
trogenous excreta Of the body. being
the chief end product, SO far as nitro
gen is concerned, Of the physiological
metabolism of the proteins and the
albumenoids of the foods. II we know
how much urea is secreted In a given
period we know approximately how
much protein has been broken down
in the body in the same time.
Next to urea and the Ammonia COM
pounds It forms, the most important
of the known nitrogen constituents Of
the urine is creatinine.
Uric acid is generally believed to
be the result Of, the daily wear and
tear Of cell constituents. the nnal re.
suit Of cleavage Of nucleoproteins.
Just what the latent adaptive powers
OF the normal human body, may be
we do not know, but inasmuch as
there is some close connection be-
tween the uric acid group and many
Of our insidious diseases, the wise man
Is using great caution in the matter Of