RICE AS FOOD. 363 



The nitrogen content of rice differs considerably less than the phos- 

 phorus content, but the more intensively a given rice is milled the 

 poorer it becomes in nitrogen ; however, the nitrogen content of different 

 classes of rice varies so greatly that this figure, in any particular case, 

 gives no indication of what treatment the grain had been subjected to in 

 milling. For practical purposes, we can distinguish three stages of 

 milling if we judge by the phosphorus content of the rice. These are: 

 (1), rice, husked only, 0.7-0.8 per cent phosphoric anhydride; (3), 

 undermilled rice, 0.45 to 0.6 per cent phosphoric anliydride; (3), over- 

 milled rice, 0.15 to 0.35 per cent phosphoric anliydride. 



Eice as food, has the following characteristics : ( 1 ) , it is comparatively 

 poor in protein ; (3), it is very rich in carbohydrates, especially in starch ; 

 (3), the white variety is low in ash and especially in phosphorus. One 

 hundred grams of rice, representing about 350 calories, contain only 

 7 to 8 grams of protein. Therefore, the daily demand for energy of 

 some 2,100 to 3,400 calories would be supplied by 600 to 700 grams of 

 rice; on the other hand, this quantity would contain only 45 to 55 grams 

 of protein; and if the grain were white, it would then afford only 1.5 

 to 3 grams of phosphoric anhydride. In fact, the quantities of the latter 

 constituent which are taken will often be still lower if other foods, rich 

 in carbohydrates or fat, are consumed in addition. 



Several authors point out the fact that a diet consisting for the greater 

 part of rice must of necessity be very voluminous. This idea is based 

 on the supposition that the rice-eating native cooks his rice in the same 

 way as the European. Scheube - has shown this to be erroneous. Our 

 own observations as well as those of other residents in the Orient prove 

 that the Japanese, Chinese, and Malays cook rice with so little water that, 

 although the grain becomes softened, it remains apparently dry. In 

 carrying on metabolism experiments, we have weighed, twice daily for 

 ten days, rice prepared by natives. This was done before and after cook- 

 ing, and we found that within narrow limits 100 grams of uncooked 

 rice gives about 350 grams of cooked rice. Rarely is more than 300 

 grams of rice, which cooked would weigh 750 grams, taken at one meal. 

 This is not a very great amount, especially when we consider that the 

 Malay at least, and, we believe, the Chinese and Japanese also, seldom 

 drink with their meals ; the majority of them drink afterward, and even 

 then only small quantities. An average European very frequentl}' drinks 

 as much as one liter of liquid with each meal, so that his meal certainly 

 is a much more voluminous one than that of the rice-eating Oriental. 



These considerations induced us to investigate the nitrogea and 

 phosphorus metabolism of people living mainly on rice or on a similar 



-Arch. f. Hxjg. (1883) 1, 352-83. 



