VIII. EFFECTS OF DEFICIENCY 301 



to interpret some of the observations and experimental findings which have 

 been made with human subjects on various fat regimens in the light of 

 fundamental facts established from experimental work with animals. Con- 

 sideration will be given to observations from studies on the use of low fat 

 diets in human subjects and to indirect evidences of possible special need 

 for fat as gained from other clinical studies. Inasmuch as correlations have 

 been found between dietary fat and the composition of the tissue lipids 

 as well as the gross and histologic alterations in dogs maintained on diets 

 with and without fat,^""^^ these data will serve as a chief source of material 

 for evaluating fat requirements for man. Reference also will be made to 

 the measurement of diene, triene, and tetraene fatty acids in blood serum 

 as a possible means for ascertaining the human requirement for these 

 fatty acids. 



1. Low^ Fat Diets in Human Beings 



Reports concerning the effect of comparatively low fat diets in human 

 subjects are meager and of a rather general nature. An attempt was made as 

 early as 1919 by von Groer^^ to determine the need of infants for dietary 

 fat. Detailed observations were made on two infants by this worker, and 

 although gain in weight was not entirely satisfactory, no striking abnormali- 

 ties developed within a period of 9 months. The low fat diet was discontin- 

 ued in one infant because of anorexia and in the second infant because of 

 infection. Holt and coworkers-^^ used a low fat diet in the study of three 

 infants. Although these studies were of short duration, one of the infants 

 repeatedly developed a skin eruption when fat was lacking in the diet. 

 In 1937, von Chwalibogowski^^ observed two infants on a low fat regimen 

 for periods of 13 to 15 months. No typical findings were evident, and this 

 led the author to conclude that fat in the diet was not essential for infants. 

 Four human subjects have been studied in our clinic and laboratories for 

 periods of 2 to 23 months. The first was one of twins who, when on a low fat 

 diet, was found to have a definitely lower iodine number of the serum fatty 

 acids than the twin infant who was maintained on a normal diet. Another 

 infant on the low fat diet developed a rather intractable impetigo but 

 showed no other clinical abnormalities. The third case concerned a rather 

 extensive study which was made on a child with chylous ascites. Beginning 



3" A. E. Hansen and H. F. Wiese, Texas Repts. Biol. Med. 9, 491 (1951). 

 3' H. F. Wiese and A. E. Hansen, Texas Repts. Bwl. Med. 9, 516 (1951). 



32 H. F. Wiese and A. E. Hansen, Texas Repts. Biol. Med. 9, 545 (1951). 



33 A. E. Hansen, S. G. Holmes, and H. F. Wiese, Texas Repts. Biol. Med. 9, 555 (1951). 

 3^ F. von Groer, Biochem. Z. 97, 311 (1919). 



35 L. E. Holt, Jr. H. C. Tidwell, C. M. Kirk, D. M. Cross, and S. Neale, J. Pediat. 

 6, 427 (1935). 



36 A. von Chwalibogowski, Acta paediat. 22, 110 (1938). 



