CHAPTER II
THE WAR-TIME IMPORTANCE OF WHEAT AND OTHER CEREALS
When the United States was called on to supply the Allies with much of its wheat and flour, we fortunately found at hand a plentiful supply of a great variety of other cereals. The use of corn was, of course, not an experiment—generations of Southerners have flourished on it. But we also had oats, rice, barley, rye, buckwheat, and such local products as the grain sorghums, which are grown in the South and West. All of them are cereals and all can be used interchangeably with wheat in our diet.
To understand clearly the value of cereals in the diet to-day, it is well to review the part played by food in general. Europe to-day is eating to live. She therefore thinks of food not in terms of menus but as a means of keeping up bodily functions, as sources of protein, carbohydrate and fat—terms seldom heard outside of the university a few years ago.
THE SIGNIFICANCE OF DIFFERENT KINDS OF FOOD
We need food first of all to burn as fuel for all the activities of the body, just as any other machine needs fuel. The fuel value of food, or its energy, is measured in calories. A calorie measures the amount of heat or energy given off when anything burns, whether it is coal in a stove or food in the body.
Practically all foods give this fuel or energy, but some give much more than others. Fats give more fuel than an equal weight of any other food. Sugar and foods rich in starch like flour and corn meal are fuel foods. This is one of the reasons why they are chosen to be shipped abroad. The cereals always supply an important part of the fuel of the diet. Watery foods, like many vegetables and fruits, normally give less fuel. A person could not live on lettuce any better than a house could be heated with tissue paper.
If the food does not supply enough energy, a person will burn up part of his own body for fuel and will grow emaciated. Far too often we find children of the very poor who are undernourished because of lack of food fuel. Sometimes even well-to-do young people half starve themselves because they get "notions" about food. One of the terrible tragedies abroad is the hundreds and thousands of men and women and children who are worn and thin and sick for lack of food.
We need food, too, to keep the organs of the body running smoothly. Abroad, people are suffering not only because they have not enough food, but because they have not the right kinds of food. Milk and vegetables and fruits are especially useful. They are the chief sources of the much-needed mineral salts and the two vitamines. The vitamines are substances of great importance about which has centred much discussion lately and which scientists do not yet fully understand, though they realize that they are essential for the growth of children and for health in adults.