Nitrogen Output.
Taken in. Nitrogen in Urine. Weight of Fæces[43] (dry).
May 18 8.119 grams. 5.75 grams.
19 9.482 6.64 15 grams.
20 10.560 8.45
21 8.992 8.64
22 9.025 8.53
23 8.393 7.69 89
24 7.284 7.34 24
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128 grams contain 6.40% N.
61.855 53.04 + 8.192 grams nitrogen.
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61.855 grams nitrogen. 61.232 grams nitrogen.
Nitrogen balance for seven days = +0.623 grams.
Nitrogen balance per day = +0.089 grams.
Average Intake.
Calories per day 2450.
Nitrogen per day 8.83 grams.
Examination of these data shows that the total amount of nitrogen
ingested for the seven days was 61.855 grams, while there were eliminated
in the urine 53.04 grams and through the fæces 8.192 grams of nitrogen,
thus showing a plus balance for the period of 0.623 gram of nitrogen. In
other words, with an average daily intake of 8.83 grams of nitrogen and
with an average fuel value of the food amounting to only 2450 calories
per day, the body was not only kept from loss, but was able to store up
a little nitrogen for future needs. Surely, one could not ask for any
better demonstration of physiological economy in nutrition than these
data, for this seven days’ period, afford.
Further, it should be mentioned, as confirmatory of the view that this
subject had long been in a condition of nitrogenous equilibrium on about
this quantity of food, that the average daily excretion of metabolized
nitrogen during this seven days’ period was 7.57 grams, while the average
daily excretion from April 13 to June 15 was 7.39 grams of nitrogen.
Finally, attention may be called to the fact that the ingestion of 8.83
grams of nitrogen corresponds to 55.18 grams of proteid food, while an
excretion of 7.57 grams of nitrogen means the metabolism of 47.3 grams
of proteid matter. A saving of more than fifty per cent in proteid food
and proteid metabolism, with maintenance of body and nitrogen equilibrium
with its possible physiological gains is not to be ignored.
* * * * *
With Jacobus, a similar trial for nitrogen balance gave the following
results: