The Unbalanced Diet of Frigid Regions.—Let us now use the table as a test of the ordinary diet in various parts of the world. Con sider first the meat diet of frigid regions. The Eskimos seem to revel in fat. When they can get it they literally stuff themselves. Sitting on the floor of their dark, smoky huts they seize it with their hands and cram it into their mouths so greedily that their faces shine with fat and their clothing is streaked with it. The Eskimo wants much fat because he needs'internal fuel to keep him warm in his far northern Sometimes the Eskimos are obliged to live for long periods on noting but fish, which are largely proteid. At such times the poor Eskimo and his family eat and eat, but are not satisfied. Their bodies clamor for carbohydrates, the intestines become deranged, and many Eskimos die from diseases induced in this way. To the dis advantage of too much fish and meat is added the great disadvantage of no cereals, vegetables, or fruits. Accordingly the people of the frigid North cannot be expected to have the endurance and stamina of the white man with his varied and nutritious diet.
Diet of Equatorial Rain-forests.—Let us now take a long jump from regions of perpetual cold to those of perpetual heat. The tropical rain-forest is subject to a disadvantage like that of the frigid regions; that is, the people often eat only one kind of food for weeks or even months at a time. For instance, where bananas can be procured they eat them day after day. Yet although they gorge themselves they cannot get enough proteid from that source, for that would require from seventy to eighty bananas a day for each person. Many equatorial people have protruding abdomens either because of the great bulk of the bananas that they have to stuff down in the effort to satisfy their hunger or more probably from the diseases thus induced. The poor quality of the food in time ruins their digestion. Equatorial people also suffer because their meals are not regular. Not only do they eat at any hour when they feel like it, but when they find plenty of food they gorge themselves, and then go hungry for days.
Diet of Tropical Jungles.—In the parts of the tropical jungle where agriculture is simplest the food is scarcely better than in the equatorial forest. The crops are such roots as the sweet potato and yam, and such fruits as the cocoanut and bananas. In such a diet starch or sugar predominates so largely that people eat ravenously, but even thus do not get enough proteids. Although an occasional pig, fowl, or goat is eaten, and some fish are caught in the streams, this happens at such rare intervals that much harm is done in the mean time.
Where the jungle people raise corn, lice, or millet the diet becomes better than in jungle regions with more primitive agriculture. Notice
in Column H of the table that corn and rice are only about half as starchy as bananas and sweet potatoes. Millet is not quite as good as corn and rice, although it is widely eaten because it can easily be raised in warm places where the rainy season is short. All three grains, however, have the advantage of not containing a great amount of water or other waste materials—only 13 per cent as appears in Column C. Therefore they do not overburden the stomach and cause digestive troubles, as does the more primitive tropical diet. Never theless, they contain twice as much starch as is advisable. More over, the lack of certain vitamines renders those who eat such a diet liable to certain diseases such as beriberi. In the majority of well populated tropical regions meat is usually so scarce and expensive that it forms no appreciable part of the diet, and there is nothing to counteract the starchiness of the other foods. In spite of this the tropical people who raise corn, millet, and especially rice, are not only benefited by the necessity of steady work, as we have seen, but by the fact that their diet is better than that of more primitive people.
Diet of Monsoon Regions.—In monsoon regions like China, for example, the commonest food is rice or millet. (See Fig. 95, Rice Map.) Since these grains are starchy, the people make great efforts to satisfy their craving for proteids. Because of the density of the population and the consequent scarcity of animals, even the less expensive meats like pork are too costly for ordinary people except at feasts or other special occasions. That is why the Chinese some times eat rats, dogs, and other animals which we despise. Perhaps we should feel differently if our supply of proteids were as limited as that of the Chinese. Fish, however, can be raised without diverting land from the crops needed by man. Hence no people in the world take more pains than the Chinese to catch fish in the sea and rivers, and raise them in ponds. In spite of this the animal food of China is inadequate. Therefore recourse must be had to plants for proteids. As legumes contain more proteids than any other vegetable foods the Chinese raise them in enormous quantities, especially beans. To render them palatable and to avoid monotony they make them into bean flour, bean macaroni, bean oil, bean curd, pickled beans, and soy, a hotly spiced sauce. Thus they obtain a fairly good diet, al though it still has too much starch and not enough proteids. More over, it has not enough fruit, for fruit seems a luxury to the Chinese, although really it is needed to round out a balanced diet.