230 



FOOD INGESTION AND ENERGY TRANSFORMATIONS. 



8 to 23 per cent with an average of 14 per cent. The maximum effect 

 for both carbon-dioxide production and heat production occurred on 

 the average between 1| a,nd 1^ hours after the food was taken. The 

 maximum for oxygen consumption was reached on the average 30 to 45 

 minutes after food. 



TABLE 172. Maximum effect of ingeslion of 100 grants of lactose on carbon dioxide, oxygen, 



and heat in respiration experiments. 



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

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

 2 Sugar taken with juice of one lemon on this day. 

 3 Same value occurs lj to 1| hours after food. 

 4 Sugar taken with juice of two-thirds lemon on this day. 

 5 3ugar taken with juice of one-half lemon on this day. 

 "Same value occurs lj to 1? and 2f to 3 hours after food. 

 "In cereal coffee (about 300 c.c. solution). 



COMPARISON OF MAXIMUM INCREMENTS OBTAINED WITH VARIOUS PURE CARBOHYDRATES. 



A comparison of the percentages of greatest increase shown by the 

 four sugars is given in table 173. The average period of observation 

 was practically the same for all of the carbohydrates, although some- 

 what less in the experiments with sucrose and the 75-gram experiments 

 with dextrose. In all cases the observation was sufficiently long to 

 obtain the maximum effect. 



The maximum increments in carbon-dioxide production for 100 

 grams of dextrose, levulose, and lactose were not far apart, being 

 25, 32, and 27 per cent, respectively, with an average maximum effect 

 of 28 per cent; with sucrose the maximum increment was 47 per 

 cent. A similar concordant effect is noted for the maximum increment 

 in oxygen consumption for dextrose, levulose, and lactose, the highest 

 values obtained being 12, 11, and 11 per cent, respectively, while with 

 sucrose it was 20 per cent. The maximum increment in heat produc- 

 tion was practically the same for dextrose, levulose, and lactose, ?'. e., 

 from 14 to 15 per cent. With sucrose it was materially greater, 24 per 



