Abstract
The importance of fat in nutrition has been known since 1929 when Burr and Burr (1) described a syndrome produced in rats by the exclusion of fat from the diet. Rats which had been reared on the diet, which was almost entirely fat-free and contained all other known essential nutrients, exhibited arrested growth, scaliness of skin and tail followed by necrosis of the tail, partial loss of hair, and damage to the urinary tract. Small amounts of lard were effective in preventing or curing the condition. Subsequently three polyunsaturated fatty acids, linoleic, linolenic, and arachidonic, containing two, three, and four double bonds respectively, were shown to have activity in curing the fat-deficiency disease (2,3) and have become known as the "essential" fatty acids (EFA).