22 FOOD INGESTION AND ENERGY TRANSFORMATIONS. 



increment due to the ingestion of food was clearly shown, the authors 

 remarking that the first meal increased the size of the combustion as a 

 result of the stimulation to the work of digestion. One year later a 

 second study of the metabolism during fasting was made with Breit- 

 haupt, and an extended report of the fasting experiments with both 

 subjects was published cooperatively by Lehmann, Mueller, Munk, 

 Senator, and Zuntz. 1 In their general consideration of the experiments 

 on food they state: 



"Im Beginn der Wiederernahrung nach langerem Hungern wachst der 

 Stoffwechsel in Folge der Verdauungsarbeit. Nachdem diese beendet, etwa 

 12 Stunden nach der letzten Mahlzeit beobachtet man niedrigere Sauerstoff- 

 zahlen als im Hunger. Der calorische Werth des Umsatzes ist aber eher 

 hoher, weil die Kohlenhydrate bei gleichem Sauerstoffverbrauch mehr Warme 

 entwickeln als Fett und Eiweiss." 2 



In the study with Breithaupt, in which the results obtained were 

 more comparable than those with Cetti, the average total heat produc- 

 tion for the two days of food before the fasting was 1,645 calories per 

 24 hours. The average of the 6 fasting days was 1,550 calories per 

 24 hours, the average of the fifth and sixth fasting days being 1,292 

 calories per 24 hours. In the 2 days with food after fasting the metabo- 

 lism increased to 1,453 calories. The average heat production for 

 two days with food, even when computed on the basis of per kilogram 

 of body-weight, was slightly above that for the last 2 days of fasting, 

 but not so large as the average for the 6 fasting days. It should be 

 stated, however, that the total amount is computed from observa- 

 tions of relatively short duration. 



Sadovyen, 1887-1888. Sadovyen, 3 using the Pashutin respiration 

 apparatus in St. Petersburg, made a series of food experiments before 

 and after fasting with one subject, a man 28 years old, with a body- 

 weight of 79 kilograms. Since the method employed was unique and 

 the place of publication obscure, the values are abstracted in table 

 3. Sadovyen concludes that there is usually a slight decrease in the 

 carbon-dioxide output during fasting and that this decrease is in pro- 

 portion to the duration of fasting. His data also lead him to believe 

 that there is no great difference between the oxygen absorbed during 

 fasting and after food, although the general decrease in the amount of 

 oxygen absorbed during fasting can be considered as having been estab- 

 lished. As is to be expected, the carbon-dioxide excretion was the 

 greatest after carbohydrates, this increase being roughly proportional 

 to the amount of carbohydrate taken. The carbon-dioxide figures, 



'Lehmann, Mueller, Munk, Senator, and Zuntz, Arch. f. path. Anat. u. Physiol., 1893, 131, 



Supp., p. 1. 

 *Ibid., p. 215. 

 'Sadovyen, Pub. Russian Soc. Gen. Hyg., 1887-88, 12. 



