352 DIGESTION AND RESORPTION OF FATS 



fat is taken up as such by the intestinal epi- 

 thelium, or y/h ether the fat is first broken up in the intestine 

 into giycerol aDd fatty acids and these components absorbed 

 in a dissolved state, to reunite into neutral fat after the 

 absorption is accomplished. 



The writer would prefer not to enter into the detailed 

 phases of this conflict of opinion here. 9 It will perhaps be 

 sufficient to state categorically that the view maintained by 

 W. Kiihne, J. Munk, M. Nencki, E. Pfliiger, 0. Frank and 

 many others, that a process of solution must precede the 

 resorption of the fat (at least of the bulk), has been upheld 

 time and again. "That the great part of the fat is split 

 before being absorbed and thereby changed into a water- 

 soluble form," 0. Cohnheim 10 believes, "is certain, and 

 there is no single ground and not a single observation to 

 prove that this is not also true of all the fat, even though 

 the negative proof that no known portion of the fat passes 

 the epithelium in emulsied form has not yet been established 

 and in fact would be difficult of establishment except by con- 

 siderations of a general nature. ' ' 



Probably it would be well to indicate the most important 

 reasons which support this view. 



Fat Cleavage and Solution of the Products of Cleavage. 

 It should be clearly understood that the fat in the intestine, 

 in by far its greatest proportion, is present, not as neutral 

 fat, but in state of cleavage, so that, especially in the lower 

 portions of the intestine, the neutral fat occurs in far smaller 

 amounts than the soaps and the free fatty acids. 



Moreover, one should keep in mind the important fact 

 (known today, but not known in the early days) that, be- 

 cause of the presence of salts of the biliary acids, of lecithin, 



9 Literature upon Cleavage, Resorption and Synthesis of Fat in the Intes- 

 tine: J. Munk, Ergebn. d. Physiol., 1, 317-323, 1912; 0. Cohnheim, Nagel's 

 Handb. d. Physiol., 2, 555, 618-621, 1907; Physiol. d. Verd. u. Ernahr., 165- 

 169, 1908; E. H. Starling, Handb. d. Biochem., 3", 226-233, 1909. 



"0. Cohnheim, Biochem. Centralbl., 1, 174, 1903. 



