You will see some foods advertised as possessing a wonderful nourishing power. Do not let such statements deceive you, for no food can have a greater nourishing power than the things from which it is made. If the particular food advertised is made from wheat flour, its nourishing power is just the same as that of an equal quantity of wheat flour. If it is made from corn meal, it can have no greater nourishing power than has the meal itself. We have learned something about the materials necessary in food and why they are needed. We must now learn why foods that contain these materials sometimes do not give us as good results as we might hope for. =Questions.= 1. What use does the body make of new cells? 2. How does the body keep itself warm? 3. Name two uses that the body makes of food. 4. What foods are especially useful for making cells? 5. What foods are chiefly used for making heat? 6. Select articles of food for two meals of equal nourishing value, one meal to be expensive and the other inexpensive. 7. How would you determine the real value of any food? =Remember.= 1. Foods are used to make heat and power in the body and to make the body grow. 2. The foods that make the body grow are called building materials, and lean meat is the best kind of building material. 3. The foods that produce heat and power in the body are called heat-producing materials, and fats and starches are the best heat-producers. 4. All vegetables contain starch, some of them contain a fatty oil, and most of them contain some building material. 5. You can get as much building and heat-producing material from cheap foods as you can from expensive foods. CHAPTER V CARE OF FOOD--MEATS [Sidenote: Value of meat as a food] Meat is one of the most important articles of our diet. It furnishes essential materials for building cells, and it furnishes fat for making heat and power in the body. [Illustration: FIG. 9. A double menace to health; the slaughterhouse is dirty, and the filth is drained into a stream.] [Sidenote: Characteristics of good meat] Since meat is so important an article of food, we should be very careful to see that it is handled in a way to keep it always perfectly clean. We should make sure that it comes from animals absolutely free from any kind of disease, and that no germs have been allowed to develop poisons in it. [Sidenote: How meat may be kept clean]