The Washington times. [volume] (Washington [D.C.]) 1902-1939, 1936-01-23
Health
Food Is Fuel
For Body
By LOGAN CLENDENNG, M. D.

We have said that the largest
part of our food intake is used,
not for replacing the brokendown
tissues of the body, but for energy.
A muscle, in contracting, does
not destroy any perceptible part
of its substance. Qn fact, as we
know from experience, muscles in.
crease in size from use)
But it does use up fuel. Like
any other machine, it depends
upon the burning, or oxidation,
of fuel to work. This fuel may
come from one or all of several
elements in the food.
Lost of its comes from the burn.
ing of sugars and Starches, and
for that reason these substances
must form the largest part Of any
diet-twice all the rest by weight.
Fats are also used for energy,
but not so readily as starches and
sugars (carbohydrates). Protein
is also used as a fuel, but probably
only after it has been converted
into carbohydrate. Most Of US
eat two or three times as much
protein as the body needs, and
this excess Is utilized partly for
energy.
There is hardly anything in all
medical science that has been so
completely worked out mathemat-
ically as this question of energy
utilization of foods. The whole
vocabulary of calories Is built
around this science.
COmmOneSt Energy
The commonest form of energy
in the world is heat, and heat, in
this sense, depends upon the
union of oxygen with some other
substance. This process is called
oxidation" which is no different
than the common word burn
ing" Almost all the energy in
the body comes from oxidation.
We do produce a little electric
energy in the nerve pathways. but
it is infinitesimal compared to the
amount Of heat energy that we
use.
In order to be scientific about
anything we have to have a
method of measurement. The
method Of measuring heat is, OF
course, by the thermometer, and
using that we get a heat unit,
which is called "calorie." A cal
orie is simply a certain amount
of heat. 1t is the amount that is
necessary to raise / kilogram of
water l degree Centigrade Cor /
pound Of water 8 degrees Fahren-
hei). Put in understandable
terms, 1 calorie is used by the
body when you rise from q sitting
position in front Of a door, turn
the key in the door, and sit down.
II you walk an hour on q level
road at the rate Of about miles
an hour, you use 160 more cal
cries than you would if you sat
still. A man $50 pounds, walking
up a flight Of stairs 10 feet high,
spends about 4 calories.
Ironing and dishwashing re.
quire about Is calorieS more than
sitting still. Scrubbing floors re-
quires so additional Galleries.
Thirty calories an hour more are
used by a typist writing at the
rate of so words a minute. A
single 16-candle lamp gives off
about IS calories an hour.
ACTIVITY
Obviously, the number Of Gallo
ries anybody uses depends upon
the weight and the amount of
activity. In general, we can say
that an adult uses about IL calo-
ries per pound in "a hours at
rest, about 20 at moderate work,
and about Is at hard work. Chill
dren require somewhat more.
This energy is supplied. as has
been said, by the three food ele-
ments- carbohydrate, fats and
proteins. Fats produce about 9
calories per gram. proteins and
carbohydrates about 4. For a man
of average weight and activity,
therefore, an average diet will
contain about 400 grams Of car.
bohydrate and about 100 grams