PROTEIN REQUIREMENT IN THE DIETARY 579 



be grown at the expense of the constituents of the soil and the pre- 

 occupation of space that might be otherwise utilized. Not only must 

 an amount of vegetable food be provided equivalent in heat-value to 

 the animal foodstuffs which we desire to synthesize, but an enormous 

 excess, to supply the radiation of heat and mechanical work performed 

 by the animal throughout the period of its growth. The Animal 

 Proteins therefore represent a consumption and expenditure of food- 

 materials totally disproportionate to their calorific value. The 

 vegetable proteins, on the other hand, are also expensive because the 

 proportion of protein in the majority of vegetable tissues, with few 

 exceptions, is extremely small. 



As a measure of national economy, therefore, if we view the matter 

 solely from a financial standpoint, a restriction of the protein-con- 

 sumption to the minimum consistent with health and efficiency would 

 seem to be highly desirable. Now the consumption of protein food- 

 stuffs and particularly of animal proteins varies very greatly among 

 different peoples. The following pre-war statistics are furnished by 

 Ostertag : 



Meat consumed 



per day per 



capita, in 



grams. 



Australia . .... >\ * ..'.. . 306 



United States of Ameri ca 149 



Great Britain ..... , . . . . . ... . . 130 



France . . -.. .*% ..... . . 92 



Belgium and Holland . ... . . . :. . . . 86 



Austria-Hungary 79 



Russia ....."... ",' . . . . . .- . ..' -. 59 



Spain 61 



Italy. . , ,V -. ...A ...;. -. ...; ":.-., :.. ....... 29 



Japan 25 



It will be observed that the consumption of meat in the English- 

 speaking countries far exceeds that which prevails elsewhere. Either 

 the English-speaking countries and particularly Australia are waste- 

 fully dissipating their food-values, or else a large proportion of the 

 population of Europe is chronically suffering from suboptimal con- 

 sumption of protein. 



The standard requirement of protein, partially derived from meat 

 and in part from vegetables and cereals, was computed by Voit to 

 be 118 grams for the average man not engaged in heavy labor, and 

 90 grams for a woman. This estimate was based upon a statistical 

 comparison of the actual consumption by presumably normal persons 

 subsisting upon a mixed diet. The necessity for this intake of protein 

 has of recent years, however, been sharply challenged by Chittenden 

 and others of the American school of physiologists and biological 

 chemists. The statistical method of estimating protein-requirements 

 is based upon the assumption of the exercise of free choice by the 

 individual and the underlying supposition is made that prevailing diets 

 represent a species of " survival of the fittest/' It is obvious, however, 



