The Nutritive Value of Pure Fatty Acid Esters*

There is an extensive literature dealing with t,he utilization by the animal body of various complex natural triglycerides, but up to the present time little attention has been paid to the separation and study of the individual fat,ty components for their ability t,o supply energy and support growth. There is no apparent reason to suppose that the individual components of a fat should be any less efficient from a nutritional standpoint than is t,he original mixt,ure. Our views concerning the metabolism of fats recognize no essential difference in the method of combustion and transport of different fatty acids. The question has taken on an added interest with the recent discovery by Burr and Burr (1) of a particular fatty acid essential for well being. The writ,er undertook to fractionate a natural fat (coconut oil) and to study its various components by feeding experiments upon rats of the Wisconsin inbred strain. Certain fatty glycerides have previously been investigated. Davis (2) fed 15 per cent of tributyrin to chickens and reported that the material was distinctly toxic. Eckstein (3) fed 15 per cent of tricaproin to rats and found good growth, although no caproic acid could be det,ected in the body fat. Powell (4) investigated tricaprylin and trilaurin by feeding these substances to adult, previously fastled rats at a 25 per cent level. She found traces of caprylic acid in the body fat’ of rats fed tricaprylin, and the body