A text-book of human physiology / by Dr. Robert Tigerstedt ... tr. from the 3d German ed. and edited by John R. Murlin ... with an introduction to the English ed., by Professor Graham Lusk.

  • Tigerstedt, Robert, 1853-1923.
Date:
1906
Catalogue details

Licence: Public Domain Mark

Credit: A text-book of human physiology / by Dr. Robert Tigerstedt ... tr. from the 3d German ed. and edited by John R. Murlin ... with an introduction to the English ed., by Professor Graham Lusk. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

    142/794 (page 106)
    creta, and determined directly from calorimetric measurement of the heat given off by the subject of the experiment. In all the experiments carbo- hydrates were given in fairly large quantities and in the calculation of the heat values it was presumed, in conformity with the current view, that they were burned first. Xow the experiments actually show a very close agree- ment between the calculated and the observed heat production. From which it follows that the theoretical presumption is a correct one, and that the total quantity of carbohydrates absorbed is burned before the body fat. Especially instructive are two series of experiments in which both the total calories supplied (2,490 and 2,489 respectively) and the quantity of proteid were the same, but where the proportion of fat to carbohydrates was consider- ably ditferent in the two. In the one experiment 94.8 g. fat -|- 247.2 g. carbo- hydrates were administered, in the other 40.3 g. fat -)- 375.2 g. carbohydrates. Direct calorimetric determination of the heat production yielded in the first 2,085 Cal., in the second 2,079 Cal., showing that the ratio of carbohydrates to fats within these limits at least is a matter of indifference to the organism. Let us see now in which direction the addition of carbohydrates will influence the total metabolism. Experiments of Pettenkoffer and Voit along this line gave the following results: Experiments. N. Food in g. G. of N excreted. Destroyed g. of Total metab- Fat. Carb. Fat.i Carb. Cal. No. 1 17.0 17.0 17.0 51.0 51.0 61.3 61.2 i6;2 4.6 10.3 17.'5 2Q.h 379 167 182 167 172 379 7.3 7.2 20.4 19.3 18.3 18.0 51.0 50.2 59.7 50.0 103.0 -56.3 379 61.0 ; -19.9 167 1,164 2 1,208 3 1,106 4 998 5 -10.9 -14.0 182 167 1,117 6 1,020 7 24.0 \ ... -38.1 1 172 36.0 - 112.9 379 1,552 8 1,649 9 1,893 10 1,782 From Experiments 1 and 2 it appears that the total metabolism after ingestion of carbohydrates (and a little fat) is not greater than it is in starvation, that carbohydrates therefore can completely replace the fat de- stroyed in starvation. From the series with 500 g. meat (17 g. N) no influ- ence of the carbohydrates on the total metabolism is indicated. With 1,500 g. of meat addition of 172 g. carbohydrates produces only a slight increase (less than ten per cent), with 1,800 g. meat, 379 g. carbohydrates produce no increase at all. ' A — sign means that fat has been stored in the body. * 1 g. N = 26.0 (25.98) Cal., 1 g. fat = 9.46 Cal., 1 g. carbohydrate = 4.1 Cal.