THE REQUISITES OF THE DIET 349 



however small its amount, from a tissue is to cause the 

 dissolution of that tissue. The integrity of the nerves 

 is maintained temporarily but at a ruinous cost. It is 

 as though a large and costly machine were to be dis- 

 mantled merely to provide bolts and screws to repair 

 another piece of mechanism. 



The period during which the tissues in general are 

 being sacrificed for the benefit of the nerves is that in 

 which the loss of weight and strength is so marked. A 

 time arrives when the internal supply of the vitamin 

 as well as the supply from the diet is insufficient and 

 the nerves can no longer be kept normal. The stage 

 of neuritis is then established. 



Other disorders besides scurvy and beri-beri are 

 almost certainly to be classed among deficiency diseases 

 and attributed to the lack of essential compounds in 

 the ration. Nutritional difficulties in infancy may be 

 examples of such conditions. There is at the present 

 time much discussion as to whether the serious disease 

 pellagra belongs in this class. It is agreed that it 

 attacks, for the most part, people whose diet is monoto- 

 nous and that liberal feeding favors recovery, but there 

 is some evidence that it may be infectious. We cannot 

 pass judgment here upon this question. 



The recognition of vitamins gives concreteness to 

 ideas that have long been held in a vague way. Many 

 years ago Sylvester Graham urged that we should 

 not carry too far the refining of food lest, in the dis- 

 carded material, we lose something of value. The 

 flour which bears his name was prepared in conformity 

 with his teaching, including, as it does, the husk as 

 well as the kernel. This was more than half a century 

 before the observations concerning the pericarp of 

 rice. 



A shrewd criticism has been passed upon sugar: 

 namely, that it is not a normal food because it has been 

 so refined as to consist of only one compound. Native 

 food products are always mixtures of numerous bodies, 



