9 



A potato, for instance, consists of 81 per cent, of water and rather more 

 than 15 per cent, of starch. Fresh peas contain 78 per cent, of water and 

 16 per cent, of starch ; and though rice or cereals are almost pure starch when 

 purchased in a dried condition, large quantities of water must be used in 

 their preparation before they are fit for food. Most fruits, such as apples, 

 peaches, or berries, contain from 85 to 90 per cent, of water and from 5 to 

 15 per cent, of sugar. 



"STOP A MOMENT," 



some one will exclaim. " You have mentioned oatmeal in two classes of food- 

 stuffs, once as an illustration of those containing body-building material and 

 then as an example of carbohydrate food. Now, which statement is 

 correct ? " 



Both are right, my friend, for, rich as oatmeal is in protein, it is even 

 richer in carbohydrates, and perhaps it may surprise you further to learn 

 that it contains fat too. It is owing to the fact that cooked oatmeal contains 

 representatives of all five classes of foodstuffs protein, fat, carbohydrates, 

 salts, and water that the Scottish nation was celebrated for its vigour of 

 mind and body when oatmeal combined with milk constituted the main 

 sources of its food-supply. 



The question also enables a passing reference to be made to 



ANOTHER POINT OF EQUAL IMPORTANCE AND INTEREST, 



which will be dealt with more fully later on, viz. : that no foods except sugar, 

 cream, and olive-oil contain only one class of nutrient. From three to all 

 five of the five classes are represented, though to a very variable amount, in 

 each form of food bread, meat, or berries, for instance ; but, for convenience, 

 it is customary to group each food in the class of which it is the most 

 representative. 



Now, we must return to the enumeration of these classes, of which the 

 next in order is the fourth, consisting of salts or mineral matters, such as 

 iron, potash, phosphorus, lime, and several more. These salts are urgently 

 needed to maintain the health of the body as well as to build its parts. If 

 the supply were to cease, so would life, even though an ample diet in all other 

 respects were provided. It is not, therefore, a matter for surprise that they 

 are found in every form of food eaten by man, as well as in most drinks, 

 water included. Their chief source of supply, however, is in cereals, 

 vegetables, and fruits ; hence the stress laid upon the inclusion in the daily 

 diet of cabbage, salads, etc. The adult human body contains about 7 Ib. of 

 these mineral matters. 



The last, but by no means the least important, class to be mentioned is 

 water. About two-thirds the total weight of the body consists of water, so 

 that its claims to constitute a class of food are immediately apparent. Water 

 must be consumed to maintain this proportion as well as to furnish the 4% 

 pints of fluid, more or less, which are given off daily from the lungs, skin, 

 and internal organs. As the body possesses a very limited capacity to form 

 water in its own tissues, most of its needs must be supplied from its diet. To 

 furnish this supply 



ABOUT HALF THE WHOLE WEIGHT OF SOLID FOOD EATEN 

 CONSISTS OF WATER, 



besides which another 2 or 3 pints should be taken daily in liquid form, 

 preferably as pure water. 



