CONSUMPTION OF FOOD IN THE HEALTHY 17 



But the enormous amount of N-retention in the forced feeding investi- 

 liions of Liithje makes us hesitate to believe that the total amount of 

 itrogen retained is really deposited as " albumin" especially as we should be 

 )rced to assume at the same time that the reserved albumin is deposited 

 )gether with a quantity of water, such as corresponds to the usual relation 

 stween albumin and water in the cellular elements of the body (one gram 

 f N =: 6.25 grams, albumin := 29.4 grams of flesh). 



According to this we should have to suppose that the N-retention of 

 49.61 grams N, which was attained by Liithje within twenty-six days, corre- 

 Donded to an albumin deposition of 935.06 grams of albumin, or a flesh 

 eposition of 4,398.53 grams. The increase in the body-weight of the person 

 sperimented on amounted to 6,070 grams during this time. If w^ estimate 

 le flesh accumulation from the N-retention, more than two-thirds of the 

 icrease in body-weight (4,398 grams) must have been due to flesh deposi- 

 on. The considerable calory excess contained in the administration of food 

 1 the days in question certainly must have resulted in a deposition of fat. 

 'he amount of this Liithje calculates in the usual manner; from the total 

 ilory excess during the entire period (29.656 calories) he deducts the calory 

 alue of the albumin which has accumulated (935.06 X 4.1), i.e., in round 

 umber 3,838 calories, and the remainder, amounting to 25.818 calo- 

 ies, is ascribed to fat accumulation. Twenty-seven hundred and seventy-six 

 rams of fat correspond to this energy value. The flesh accumulation of 

 ,398 grams, and a simultaneous fat deposition of 2,776 grams coincide 

 ery imperfectly with an increase in weight of only 6,070 grams. This may, 

 owever, be readily explained by the assumption that the body during the 

 lasting period lost a weight of water, corresponding to the difference (1,104 

 rams). 



In the feeding experiments of Krug, the same difference was noted, 

 i^ith an increase in weight of only 3,100 grams, the albumin accumulation of 

 ,455 grams calculated from the retained N, and the fat accumulation from 

 le calory excess after deducting the albumin calory, amounted to 2,254 

 rams. Krug assumed without more ado that the body lost 609 grams of 

 ater. 



This assumption is certainly justifiable, and a decrease in water during 

 Dreed feeding appears quite plausible if we remember that each increase of 

 le albumin metabolism (for example, by a large albumin meal) is soon fol- 

 )wed by a decided excretion of water. 



In my opinion the assumption of so large a loss of water is, however, unnec- 

 ssary. In the previously mentioned calculations, we have always proceeded 

 a the assumption that the total calory excess of the food not used to store 

 p albumin must be utilized in fat formation. It has, however, not been con- 

 dered that an excess of food also invariably increases the total metabolism, 

 ad, it may now be supposed, increases this out of proportion to the intestinal 

 ibor. A true luxury consumption of non-nitrogenous food substances takes 

 lace. Only a portion of the superfluous food energy is utilized in accumu- 

 ition; in man another portion, probably showing individual variation, under- 

 oes combustion, and is utilized in heat production, the organism replying 



