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his bread and cheese (carbo hydrates, fat and albuminoids), and many 

 others, exemplify this inference. 



2. Starch, sugar and f.its are essentially heat and energy producers. 

 As heat producers fats are about 2^ times more valuible than carbo- 

 hydrates. In cold climates we find the inhabitants existing largely on 

 fatty foods. Esquimaux and lumbermen are notable examples. 



The albuminoids are the most costly of all the nutrients. While 

 performing to some extent the functions just mentioned, they have for their 

 chief office that of building up the tissues of the body and repairmg 

 the waste continually going on. The albuminoids cannot be replaced 

 in the diet by any other material. 



3. Fruits and many vegetables while not rich in nutritive material 

 should form a large part of the diet, as they assist in digestion and, 

 acting medicinally, give a healthy tone to the system. Salads of lettuce, 

 celery and beets, if not too rich, have a cooling and refreshing effect. 



4. Condiments and stimulants are often desirable as appetisers 

 and in moderate amounts excite the flow of the digestive fluids, and 

 thus aid digestion. Excess of alcohol, tea and certain other articles of 

 this class is well known to have injurious physiological action. 



5. Cooking, while, as a rule, rendering the animal foods rather less 

 digestible, makes vegetable foods more fit for consumption. 



6. Mastication should be thorough in order that the food may be 

 well mixed with saliva, and tor this purpose slow eating is to be 

 recommended. 



7. The process of digestion is a continuous one. Active work 

 retards somewhat the digestion of a heavy meal, and such should, 

 therefore, be taken rather after the work of the day than during it. The 

 times of meals must largely be regulated by the amount and kmd of 

 work. It is better to eat a little and often than to overload the digestive 

 apparatus at any one meal. Though the digestive process is not so 

 vigorous during sleep as in the d.,iy time, light refreshment is to be 

 recommended before retiring — the stomach thereby is kept from being 

 totally void of food in the morning. To those who are not robust eaters 

 this advice is more particularly given. 



8. The blood which conveys the digested food to every part of the 

 body is largely water. On this account and because all the tissues contain 



