c 



A'illU cm. 

 68 THE PROTEIN ELEMENT IN NUTRITION 



made of Chittenden, who, in first stirring the nutritional pool 

 by the publication of his two well-known volumes, has done 

 more to awaken interest, stimulate research, and lift the 

 subject of dietetics from the playground of quacks and charla- 

 tans, than perhaps any of his predecessors. That good will 

 eventually accrue from the extensive investigations that have 

 followed on the publication of Chittenden's studies cannot be 

 doubted, and it may be hoped that before long the whole subject 

 of dietetics and food requirements may be lifted out of the vale 

 of empiricism, in which it has hitherto lain, and raised to one of 

 those pinnacles of fame reserved for the exact sciences. 



DIETAEY STANDARDS. 



Many different methods have been employed in the determina- 

 tion of the gross amount of food consumed per capita of the people 

 of different countries. A rough average may be obtained from 

 a statistical survey of the amount of food materials available 

 certain factors for waste being taken into consideration this 

 amount divided by the total population will give a figure which 

 represents a general average, but which is of little use where 

 anything approaching accuracy is demanded. Russell* has 

 collected a great mass of information on the foodstuffs, diets, 

 and physical characteristics of different races and nations which, 

 although of great interest from many standpoints, is not sufficiently 

 detailed to be of any great service in arriving at the quantities 

 of the proximate principles present in the different dietaries. 



A more accurate method of obtaining the desired information 

 is by means of what has been termed dietary studies ; in these 

 individuals, or groups of individuals, are kept under observation, 

 the total food consumed is carefully recorded, samples analyzed, 

 and the value of the dietaries in protein, carbohydrates, and fat 

 computed. This method may be undertaken when there is free 

 selection of food, or, as in public institutions, where the choice 

 of food is limited. 



More accurate methods are those where the subjects under 

 observation are placed under suitable conditions for the analyses 

 of the food and excreta over a stated period ; again, there may 

 be free choice of food, or, if the intention is to study the effects 

 of different food materials, the choice may be limited. The 

 most laborious, but at the same time the most accurate, method 



* Russell, " Strength and Diet," London, 1905. 



