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A TEXTBOOK OF PHYSIOLOGY 



Animals e.g., pigeons fed upon polished rice gradually lose 

 weight, develop nervous symptoms akin to beri-beri, and die. Post 

 mortem extensive changes are found in the cells of the central nervous 

 system, and inflammatory changes in the nerve trunks. 



A similar substance is included in the husks and germ of the wheat 

 berry. White flour made from the wheat berry from which the bran 

 (the outer husk), the sharps (the under husk), and the germ have 

 been removed, will not support life by itself. Neither will bread made 

 from it; while wholemeal bread will. 



The possession of this substance accounts for the superiority of 

 " standard " and particularly of wholemeal bread over " white " 

 bread. By the children of the very poor, who live mainly on bread 

 and margarine, it is imperative that wholemeal bread should be eaten. 



FIG. 189. To SHOW EFFECT OK VITAMINES ON GROWTH. (After C. Funk.) 

 These chicks are of the same age, the smaller fed on a diet deficient in vitamines. 



The anti beri-beri vitamines have been found to occur in yeast, in 

 various vegetables, and in milk; they are not destroyed by heating 

 to 100 C., but are destroyed at 120 C. 



There are also anti-scorbutic vitamines, the lack of which cause 

 scurvy. These are destroyed easily by cooking or preserving, hence 

 the advantage of raw fruit or salads in the diet. Potatoes, fresh 

 vegetables, oranges, and fruit not too ripe are rich in these vitamines. 

 The introduction of the potato has expelled scurvy from the towns. 

 In addition to the above there is a fat-soluble vitamine essential to 

 growth present in butter and animal fat margarine, but not in vege- 

 table oil margarine or lard, present also in g.een vegetables which 

 form the complete food of an herbivorous animal. 





