DIET UNDER VARIOUS CONDITIONS 357 



a correspondingly less intake of energy as food. If they take as 

 much, they grow fat. 



Climate. Cold increases the activity i.e., the amount of muscular 

 work performed heat diminishes it. In cold climates there should 

 therefore be an increase in the energy intake, particularly in the form 

 of fat, which, owing to its high caloric value, is very heat-giving. In 

 the tropics, on the other hand, food must be cut down, particularly 

 protein owing to its high specific dynamic energy. The diet of natives 

 in Singapore averages 60 grms. protein, 35 fat, and 20 carbohydrate, 

 with an energy value of about 1,600 calories. 



The Nutrition of the Foetus. During pregnancy, the embryo is 

 nourished at the expense of the mother through the placenta. It is 

 during the last three months of pregnancy that the great increase in 

 weight of the foetus occurs; at the same time, the mother's oxygen 

 use increases about 25 per cent, above the normal. Calculation shows, 

 however, that not more than 10 grammes of dry matter per day are 

 required for adequate growth of the foetus. Analysis of the full-time 

 foetus shows that an average child of 7 pounds contains nearly 400 

 grammes of protein, 300 grammes of fat, and 83 grammes of mineral 

 ash, chiefly calcium and phosphoric acid. In regard to the question 

 of the diet of the mother, therefore, it is obvious that no excessive 

 demands are made upon her in the matter of food intake. Special 

 diets are not required by the pregnant woman. All that is required 

 is a slightly increased intake of simple protein and lime-giving foods-, 

 such as meat, milk, eggs, cereals, fruits, and vegetables. The more 

 nearly a mother lives a normal healthy life, the better it is for the foetus. 



The Nutrition of the New-born Infant. The new-born infant should 

 be fed, if possible, by its mother. Every mother should do, and should 

 be encouraged to do, all in her power to suckle her own infant. The 

 mother's milk is best adapted to the needs of the growing child. It is 

 sterile ; it contains the right kinds and proportions of protein, 

 lecithin, and salt3. It has been shown that there is a proportion 

 between the composition of the mother's milk and the rate at which 

 the young grow. This is especially marked in quickly growing animals. 

 Thus, a puppy doubles its weight in eight days; its mother's milk 

 contains 7-1 per cent, of protein and 1-3 per cent, of ash. A child 

 takes six months to double its weight; human milk contains but 

 1 -5 per cent, of protein and 0-2 per cent, of ash. The lecithin-content 

 of the mother's milk varies somewhat with the relative weight of the 

 brain to the body weight. Relatively, the larger the brain the bigger 

 the lecithin-content of the mother's milk. In the calf the brain 

 weight to body weight is 1 : 370; in the puppy, 1 : 30; in the new-born 

 child, 1:7. In proportion, the milk of the different mothers contains 

 lecithin in percentage of the total protein 1-4, 2-11, and 3-05 respec- 

 tively. It is well adapted to the child's digestive powers, and, what 

 is also important, it contains bodies capable of increasing the child's 

 immunity to any ailments which may befall it in early life. This last 

 point was proved by the following ingenious Ci changeling " experi- 



