INGESTION OF CARBOHYDRATES. 



237 



experiment with H. L. H., on June 7, 1911, which included a later 2- 

 hour period, approximately 1 gram additional was excreted. The 

 excess consumption of oxygen ranged from 1.8 to 6.4 grams, with an 

 average of 4.3 grams, while the excess heat production varied from 10 

 to 22 calories, with an average of 18 calories. No experiments were 

 made with less than 100 grams of lactose. 



TABLE 177. Total increment of carbon dioxide, oxygen, and heat following ingestion 

 of 100 grams lactose in respiration experiments. 



'Period from the time when subject finished eating to the end of the last observation, except 

 in cases when the increment of heat ended earlier. See tables 164 to 168 for complete observations. 

 '13.2 grams for 5 h 31 m . 



COMPARISON OF TOTAL INCREMENTS IN METABOLISM OBTAINED WITH VARIOUS PURE 



CARBOHYDRATES. 



A comparison of the several carbohydrates in their effect upon the 

 metabolism can best be made by a tabular presentation of the averages 

 for the total increments obtained with the different carbohydrates in 

 this series of experiments. Such a grouping has been made in table 

 178. Comparing particularly the increments for the 100-gram amounts, 

 we see that the differences in the average total increments in the carbon- 

 dioxide production are not so very large. The effect is most pro- 

 nounced with levulose and least with lactose, that for sucrose lying 

 between the levulose and dextrose increments. According to the 

 standards used in the earlier studies of carbohydrates, in which special 

 emphasis was laid upon the carbon-dioxide excretion, it would be con- 

 sidered that the effect with levulose was much more pronounced than 

 that with sucrose and that the sugars affected the metabolism in these 

 experiments in the decreasing order of levulose, sucrose, dextrose, and 

 lactose. At first sight it is difficult to explain why the carbon dioxide 

 produced should vary for the several sugars, and it is clear that the most 

 careful analysis of the effect of sugar ingestion on the metabolism 

 should not be based upon carbon-dioxide production. An examina- 

 tion of the increments in oxygen consumption shows that in this case 

 the maximum increment was obtained with sucrose, the order of effect 



