EVIDENCE AS TO THE FORMATION OF FAT 295 



nitz injected iodifin, a stable compound of iodine and fat, and found 

 it secreted in the milk, an observation which has been confirmed on 

 woman. 



Caspari likewise fed a bitch on iodised fat and found 23 per cent, 

 of this appeared in the milk. If much rice or sugar were also fed 

 no less than 32 per cent, of the iodised fat passed into the milk. 

 The greater part of the remainder became stored in the fat depots. 

 He then fed with lard, and found 8 per cent, of the iodised fat stored 

 in the depots passed into the milk. From this observation he con- 

 cluded that the milk fat comes from both the food and the depot 

 fat. It has been objected to this conclusion that when iodised casein 

 is fed, a measurable amount of iodised fat appears in the milk. 

 This does not prove that the casein is converted into fat. Probably 

 the body or food fat robs the casein of its iodine, when the latter 

 undergoes decomposition during or after absorption. 



There can be no doubt, then, that milk fat can come from food 

 or body fat. It can also come from carbohydrate food. Jordan 

 and Jenter placed a strong Jersey cow in the height of lactation 

 on hay and seed food, from which the fat had been largely ex- 

 tracted. In ninety-five days they estimated the cow assimilated 

 only 5-7 Ibs. of fat, yielded 62-9 Ibs. of butter, and increased 47 Ibs. 

 in weight. It excreted urea equivalent to the decomposition of 

 33-3 Ibs. of proteid. The non- nitrogenous moiety of this amount 

 of proteid could at most have produced only 17 Ibs. fat. Granting 

 the fact, which is unproven, that this amount of fat could have been 

 derived from proteid, it is clear that the rest must have come out 

 of carbohydrate food, seeing that body fat was not lost but gained. 



The formation of sebum has been supposed to be an example 

 of fatty decomposition of the cell proteid, but it is now recognised 

 that it is a secretion which stands in close relation to the depot 

 fat (Plato). By feeding geese with sesame oil this fat was found 

 secreted by the rump gland. 



PATHOLOGICAL EVIDENCE AS TO THE FORMATION OF FAT FKOM 



PROTKID 



Histological examination has led to the widely accepted theory 

 of fatty degeneration of the cell proteids (Virchow), but chemical 

 analysis of the tissue does not bear this out. The fat previously 

 existent in the cells comes prominently into view in the degenerated 



