372 ARON AND HOCSON. 



While it is not possible to establish an exact phosphorus minimum, 

 just as it is impossible to establish a nitrogen minimum, our experiments 

 show that an intake of less than 1.65 grams of phosphorus per 50 kilo- 

 grams of body weight, or 0.033 grams phosphoric anhydride per kilogram 

 is- insufficient to cover the demand of the body for phosphorus. The 

 quantities given by most authors ^* are considerably higher than this figure. 



We discussed the fact that the phosphorus content of rice is of very 

 great physiologic importance, in the introduction to this paper. Experi- 

 ments numbered 4, 5, and 7 show conclusively that a diet consisting 

 of white rice, bread, bacon, and other foodstuffs poor in phosphorus does 

 not cover the demand of the body for that element, even with the addition 

 of small quantities of fish. (See experiments numbered 12, 13, and 

 14.) However, the phosphorus balance becomes positive if unpolished 

 rice, rice bran, or phytin is added to the food. (See experiments num- 

 bered 3, 6, and 11.) A comparison of experiments numbered 3 and 4 

 very plainly shows that the body loses phosphorus when oh a diet consist- 

 ing mainly of white rice, while on the same diet, red rice being substituted, 

 the amount of that element exceeds the demand of the body. The distri- 

 bution of phosphorus in urine and faeces is not of as great importance 

 as in the case of nitrogen, because the phosphorus excreted in the faeces 

 consists in part of that which has previously been absorbed and again 

 excreted in the lower parts of the large intestines. It should be noted 

 that those experiments where the amount of phosphorus taken was high 

 show that the excess is excreted almost entirely in the faeces. 



Our figures seem to show that the phosphorus demand of Filipinos (Malays) 

 is lower than that given, by other authors. It may be that the body becomes 

 accustomed to a lower supply of phosphorus than that usually considered to 

 be necessary, and the high results in the metabolism experiments on Europeans 

 might simply be requirements of "luxury." Another view seems not too far 

 removed: Several authors have argued that there is a connection between mental 

 work and phosphorus metabolism. 'Of course, the belief of older investigators, 

 that mental work increases metabolism in the brain, which is rich in phosphorus, 

 has been shown to be absurd. The quantity of phosphorus in the brain itself 

 is much too small as a whole to influence the phosphorus metabolism of the 

 body. However, the nervous system might have a regulatory influence on all 

 the dissimilative processes in the body, so that what we might term the "tone" 

 of the "catabolic cell-metabolism" could be increased during intensive activity 

 of the nervous system and lowered during rest. We have based this consi- 

 deration especially on the very striking results of experiments by Folin and 

 Shaffer. If such a view has any basis in fact, then the "tone" of the cell 

 metabolism of the ordinary Malay, with his phleg-matic temperament, must be 

 very low. Such a conclusion fs somewhat startling. Once considered, it was 

 necessary to attempt to demonstrate whether a difference in the destruction of 



"Oeri, Ztschr. klin. Med. (1909), 67, 288, 306; Ehvstrohm, Skatid. Arch. Phys. 

 (1903), 14, 91; Renoall, Skand. Arch. Phys. (1905), 16, 94-138; R. Tigerstedt, 

 Handbuch d. Phys. {TiJugel) ( 1908), 1, 530. 



