GENERAL METHODS HISTORY OF PROTEIN FOOD. 913 



pected result may be illustrated best by reference to the condition 

 known as beriberi. Beriberi is a disease that occurs chiefly among 

 oriental nations that make great use of rice as a food. The dis- 

 ease takes a variety of forms, but the characteristic symptoms are 

 paralyses, and atrophy and contractures of the limbs. It has been 

 shown that the condition is caused by limiting the diet exclusively 

 or mainly to polished rice, that is, to rice from which the outer 

 layers of the grains have been removed. If the polishings are 

 restored to the diet the condition disappears, or if other materials, 

 such as meat and barley, are used with the polished rice the disease 

 does not occur. The interpretation placed upon these results 

 is that the polishings contain some constituent essential to body- 

 metabolisms. This conclusion has been much strengthened by 

 experiments on fowls. When these animals are fed exclusively on 

 polished rice they develop a condition (polyneuritis) similar to 

 beriberi and soon die. They may be saved by adding the polishings 

 to the diet or by changing the diet. Funk has shown that from 

 the polishings of rice, and from many other of the ordinary foods, 

 there can be isolated a relatively simple nitrogenous base which 

 seems to resemble in structure the pyrimidin bases found as one 

 component of nucleic acid.* He designates this base as vitamine, 

 and experiments show that when administered to an animal or 

 patient exhibiting the symptoms of beriberi these symptoms dis- 

 appear. The new ideas suggested by the facts known in regard 

 to beriberi have been supplemented by much interesting work 

 upon the effect of various diets upon growth and maintenance, 

 particularly work done in this country upon white rats by Osborne 

 and Mendel f and by McCollum and his co-workers. McCollum { 

 concludes that there are two, and, so far as our positive knowledge 

 goes, only two of these essential accessories present in our natural 

 foodstuffs. Inasmuch as their chemical nature is unknown at 

 present, he designates them provisionally as "fat-soluble A" and 

 "water-soluble B." The latter corresponds with Funk's vitamine. 

 It is soluble in alcohol as well as water, is very widely distributed 

 in our natural foods, but is absent from such substances as purified 

 sugar or starch. It is the lack of this accessory in polished rice 

 which makes this material, when taken alone, an inadequate diet. 

 If the rice is used together with other foodstuffs, animal or vege- 

 table, the water-soluble accessory is provided by the latter and the 



* For a general statement with literature see Funk, "Ergebnisse der Phys- 

 iologic," 13, 125, 1913. 



t Osborne and Mendel, "Journal of Biological Chemistry," 15, 311, 1913; 

 16, 423, 1913, and Osborne and Wakeman, ibid.> 21, 91, 1915. 



t McCollum and Davis, "Journal of Biological Chemistry," 23, 23, 1915; 

 see also McCollum, Harvey Lecture, 1917, "Journal of the American Medi- 

 cal Association, May 12, 1917. 



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