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METABOLISM IN STARVATION. 893
of the unit of the weight of the body, namely, 1 kilo—is, on the contrary,
greater in small animals than in larger ones. The reason for this is that
the smaller animals have a greater surface of body in proportion to their
mass than larger animals, and the greater loss of heat caused thereby
must be replaced by a more active consumption of material.
It follows from the decrease in the weight of the body that the absolute
extent of metabolism must diminish in starvation. If, on the contrary,
the extent of metabolism is referred to the unit of weight of the body,
namely, 1 kilo, it appears that this quantity remains almost un-
changed during starvation. The investigations of Zuntz, Lehmann,
and others,1
on the professional faster Cetti, showed on the third and
sixth days of starvation an average consumption of 4.65 cc. oxygen per
kilo in one minute, and on the ninth to eleventh day an average of 4.73
cc. The calories, as a measure of the metabolism, fell on the first to
fifth day of starvation from 1850 to 1G00 calories, or from 32.4 to 30 per
kilo, and it remained nearly unchanged, if referred to the unit of body
weight.2
In man the average daily energy consumption in starvation
amounts to about 30-32 calories per kilo.
The extent of the metabolism of proteins, or the elimination of nitrogen
by the urine, which is a measure of the same, diminishes as the weight
of the body diminishes. This decrease is not regular or the same during
the entire period of starvation, and the extent depends, as the experi-
ments made upon carnivora have shown, upon several circumstances.
During the first few days of starvation the excretion of nitrogen is greatest,
and the richer the body is in protein, due to the food previously taken,
the greater is the protein catabolism or the nitrogen elimination, accord-
ing to Voit. The nitrogen elimination diminishes the more rapidly
—
that is, the curve of the decrease is more sudden—the richer in proteins
the food was which was taken before starvation. This condition is
apparent from the following table of data of three different starvation
experiments made by Voit 3 on the same dog. This dog received 2500
grams of meat daily before the first series of experiments, 1500 grams of
meat daily before the second series, and a mixed diet relatively poor in
nitrogen before the third series.
Day of Starvation.
grams of Urea Eliminated in Twenty-four Hgurs.^
First 60.1
’
26.5
’
13.8
Second 24.9 18.6 11.5
Third 19.1 15.7 10.2
Fourth 17.3 14.9 12.2
Fifth 12.3 14.8 12.1
Sixth 13.3 12.8 12.6
Seventh 12.5 12.9 11.3
Eighth 10.1 12.1 10.7
1
Berlin, klin. Wochenschr., 1887.
2
See also Tigerstedt and collaborators in Skand. Arch. f. Physiol., 7.
1
See Hermann’s Handbuch, 6, Thl. 1, 89.
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