FACTORS ALTERING NUTRITIOXAL VALUE 915 



10.9 lb., while the corresponding increase was 30.3 lb. when an isocaloric 

 diet containing hydrogenated soybean oil and lecithin was fed. 



f . Experiments on Children: Leichenger, Eisenberg, and Carlson^^'' 

 made a comparative study of the growth of orphanage children who re- 

 ceived either a vegetable margarine only or butter only as a table spread. 

 This experiment lasted over a two-year period. Although this is a rela- 

 tively short interval in the life-span of the human, the experiments were 

 sufficiently decisive to lea\o no question as to their interpretation. It w^as 

 demonstrated that the well-being of the children, as well as their growth (as 

 determined by measm'ements of weight and height), were similar in the 

 two groups during the test. These data would seem to indicate that the 

 results obtained on rats are applicable to the human. 



g' . The Relationship of the Vaccenic Acid Content to the Alleged Superior 

 Growth-Promoting Activity of Butter: The Boer group suggested that 

 the greater growth rate of rats on butter-containing diets, as compared 

 with those receiving rapeseed oil or olive oil in their diets, could be traced 

 to the presence of a particular fatty acid in butterfat, namely vaccenic acid, 

 or 11-octadecenoic acid. Boer, Jansen, and Kentie^*^^ were the first to ob- 

 serve that summer butter contains appreciable amounts of an unsaturated 

 fatty acid which is absent from winter butter, as well as from vegetable 

 fats. This acid was identified as vaccenic acid, and its presence in butterfat 

 and in other fats has since been established by several investigators. ^^^~^" 

 Although vaccenic acid was not found as a component of vegetable fats, 

 it has been reported in hydrogenated vegetable fats such as margarine. ^^^-^^^ 

 Considerable experimental evidence now refutes the hypothesis that vac- 

 cenic acid has a specific effect upon growth. 



Vaccenic acid was identified as the specific nutritional adjunct in butter, 

 not only on the basis of its presence in this fat,^"^ but also due to the demon- 

 stration of an increased gain-in-weight of rats receiving a rapeseed oil diet 

 when vaccenic acid obtained from China wood oil was added to the rape- 

 seed oil.^^^'^^^ It was further suggested by Boer et al.^^^ that the failure of 

 Euler and co-workers^^^'^""* to confirm the earh^ results of Boer^°^ and of 



33^ H. Leichenger, G. Eisenberg, and A. J. Carlson, J. Am. Med. Assoc, 136, 388-391 

 (1948). 



'^ S. H. Bertram, Biochem. Z., 197, 4:33-441 (1928). 



"« J. Gros.?feld and A. Simmer, Z. Untersuch. Lebensm., 59, 237-258 (1930). 



=>" R. P. Gever, H. Nath, V. H. Barki, C. A. Elvehjem, and E. B. Hart, /. Biol. Chem., 

 169, 227-228 ilM7). 



338 J. Boer, B. C. P. Jansen, A. Kentie, and H. W. Knol, /. Nutrition, 33, 359-360 

 (1947). 



3" J. Boer, B. C. P. Jansen, and A. Kentie, Nature, 158, (1946). 



3« B. V. Eukr, H. v. Euler, and I. Siiberg, Ernahrung, 8, 257-264 (1943); Ch^m. Abst., 

 35,4921-4922(1945). 



