FOODS AND THEIR PHYSIOLOGICAL VALUE. 321 



proteids needed either at work or at rest was about the 

 same. They did not, however, increase the amount of fat 

 given when working, but made the increase in the carbo- 

 hydrates, and then found that under such circumstances 

 the man to be satisfied consumed much larger quantities of 

 these. 



Similar experiments were tried on a young physician, 

 whose diet in one day consisted of: 



127 grams of proteid. 

 89 grams of fat. 

 362 grams of carbohydrates. 



As average figures, therefore, the following little table may 



suffice : 



Water 3,000 grams. 



Proteids 131 " 



Fats 88 



Carbohydrates 400 " 



In such an average diet there are 20 grams of nitrogen and 

 312 grams of carbon. This proportion is about the propor- 

 tion normally desired by the body. These 20 grams of ni- 

 trogen could be secured from the following amounts of 



foods : 



Cheese- 272 grams. 



Peas 520 " 



Lean meat 538 



Wheat flour 800 



Eggs 900 (about 18 eggs.) 



Milk 3,000 



Potatoes 4,600 



Turnips ~ 8,700 



A glance at the figures just shown will give at once the 

 relative nutritive value of the main foods. Cheese, consist- 

 ing almost wholly of casein and being in tolerably compact 

 form, is probably by weight the most nutritious. Eggs, on 

 the other hand, in spite of our notion that they are so nu- 

 tritious, would not yield to the body the required amount 

 of nitrogen unless the diet should average eighteen or more 

 eggs per day. In order to get sufficient proteids out of a 

 diet of potatoes it would require the consumption of a per- 

 fectly unwieldy lot, while if the attempt should be made to 

 21 



