Biopotencies of the Essential Fatty Acids

Linoleic, linolenic, and arachidonic acids have been recognized as the chief polyunsaturated fatty acids which possess an appreciable bio- 

Proof of the Inability of Animals to Effect a Biosynthesis of the Polyunsaturated Adds 

The necessity of polyunsaturated fatty acids as dietary components is to be ascribed to the fact that they cannot be synthesized by the animal de novo. If they are absent from the diet, tissues in which they play an integral role and enzyme systems in which they may participate will become depleted. They will then function less effectively, or they may disappear entirely. 

In sharp contrast to the ease of synthesis of the monoethenoid acids from the corresponding saturated fatty acids, Bernhard and Schoenheimer (1940) demonstrated in an unequivocal manner that the rat is unable to synthesize either the diethenoid acid, linoleic, or the triethenoid acid, linol c, from carbohydrate, although large amounts of stearic and palmitic acids were shown to originate concomitantly from this foodstuff. Thus, saturated and monoethenoid acids, which have most important functions in the animal, are considered to be nonessential from a dietary standpoint, since they can be synthesized even on nonfat diets. On the other hand, linoleic, linolenic, and arachidonic acids are regarded as essen- 

The Question of the Possible Biopotency of Oleic Add and Other Monoethenoid Adds 

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