About two years ago, Hansen1 conceived the idea of investigating the possible clinical bearing of a discovery made in 1929 by Burr regarding the requirement for unsaturated fatty acids in animal nutrition. Burr found that rats placed on completely fat free diets, but adequate in all other respects, soon developed a definite syndrome characterized in the early stages by scaliness of the skin and in the later stages by cessation of growth, necrosis of the tail and pathologic alterations in the kidneys. When, however, he added fats to the diet of these experimental animals, they again began to grow and the skin scaliness disappeared entirely.
Hansen found that the iodine absorption value of the blood serum of eczematous babies is low and that it increases with clinical improvement. He could produce an increase in the serum iodine by feeding these babies linseed oil and he also reported a number