DIETETICS 345 



2. The proper selection of food materials to supply such an adequate 

 diet, including the economic purchase of the same. 



3. The various methods of preparing food for consumption. 



4. Food hygiene. 



Much study has been expended upon the question of the adequate 

 dietary. There is a general consensus of expert opinion that all three 

 classes of foodstuffs should enter into the dietary of man, the amount 

 and proportion of these being regulated according to conditions of 

 age, sex, activity, and environment. In the table on p. 343 are shown 

 a few of the diets suggested by various authorities, the weights being 

 given in the dry condition of the foodstuffs: 



The chief point of interest in the above is the amount of protein 

 required in the adequate diet. It is generally conceded that the 

 amount of protein required is from 100 to 120 grammes. The following 

 diets have been suggested for temperate climates as the result of recent 

 work. The values are given for food as purchased. 



Protein. Fat. , <** Calories. 



The work done by an ordinary labourer is estimated to be 100,000 

 kg. metres, 2000 calories can be taken as the maintenance requirement 

 of the resting man. The mechanical equivalent of heat 4-23 kg. m.= 

 1 calorie. The efficiency of a man as machine is taken as 20 per cent. 

 The fuel value of the food spent on work is then about 1200 calories. 



The peace dietary provided to the British Army is supplemented 

 by food bought for supper, and the pay is now sufficient to enable 

 this to be done without hardship. Experience seems to show that 

 the plan of letting the men buy their own supper works smoothly r 

 and is preferred ; it gives elasticity to the diet, and allows each man 

 to select the quality and amount of food which suits him. The recruit 

 a growing lad requires more food, and the Army Council have wisely 

 granted him a messing allowance. H usually buys considerable quanti- 

 ties of cakes. The war rations of the British Army in South Africa 

 may be contrasted with that of Japan and Russia in Manchuria: 



British 



Japanese 



Russian 



