CHAPTER V 



NUTRITION IN MAN AN INTRODUCTION TO THE STUDY OF PELLAGRA 

 AND HUNGER EDEMA 



From what has been brought out till now, it is clear that in nutri- 

 tion, it is not sufficient that all the known dietary constituents be 

 present; they must also bear the proper relationship to each other. 

 This idea developed chiefly through observations on rats. If these 

 animals are given a qualitatively correct diet (ad libitum), dietary 

 deficiencies develop nevertheless. It would be tempting to assume 

 that these animals need only ingest more food in order to receive 

 all of the constituents in correct amounts. In practice, however, it 

 is evidently not the case. No matter how much food the animal eats, 

 the relationship of the individual components is not altered. This 

 excessive dilution of certain components may appear in human nutri- 

 tion, and yield a rather unclear etiological picture. 



Pellagra, sprue, hunger edema, and perhaps carbohydrate dys- 

 trophy in children, may be associated with the above condition. At 

 least two of the diseases mentioned have recently been attributed to 

 the lack of a protein of high biological value. A number of animal 

 proteins are generally regarded as such. Should this conception 

 prove to be correct, then these pathological conditions must be 

 stricken from the list of avitaminoses, which has in fact already 

 been done by some investigators. We feel, however, that these 

 diseases have been cleared up so little, etiologically, that this pro- 

 cedure seems to us altogether unjustified at present. In the last 

 war, nutrition played a greater role than has been generally assumed 

 by the laity. At the time of the war, we saw one immense metabolic 

 experiment, from which a great number of conclusions could have 

 been drawn, if the serious situation had not prohibited a cold-blooded 

 survey. The late pharmacologist, Meltzer, remarked at one time 

 that all scientific data obtained during the war would have to be 

 corroborated after the war. He may have been correct in this state- 

 ment, though the convincing power of the large involuntary nutri- 

 tional experiment remains unquestioned, and we may draw a number 

 of conclusions for our purpose. Various problems must be taken 



into account in this connection, namely: 



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