6. The minerals in the body are salt, lime, iron, soda, and potash.
CHAPTER III
DIGESTION OF FOOD IN THE MOUTH
11. Food of the cells.—All the cells of the body work and wear out. They must eat and keep growing. The food of the cells is the blood. Water, albumin, fat, sugar, and minerals are in the blood. The cells eat these things and grow. All food must be one or more of these five things. Before they reach the blood, they must all be changed to a liquid. A few cells of the body are set aside to do this work of changing them. Changing food into blood is digestion.
12. Cooking.—Cooking begins digestion. It softens and dissolves food. It makes food taste better. Most food is unfit for use until it is cooked. Poor cooking often makes food still worse for use. Food should always be soft and taste good after cooking. Softening food by cooking saves the mouth and stomach a great deal of work. The good taste of the food makes it pleasant for them to digest it. We must cut our food into small pieces before we eat it. If we eat only a small piece at a time we shall not eat too fast. If we cut our food fine we can find any bones and other hard things, and can keep them from getting inside the body.
13. Chewing.—Digestion goes on in the mouth. The mouth does three things to food. First, it mixes and grinds it between the teeth.
Second, it pours water over the food through fine tubes. The water of the mouth is called the saliva. The saliva makes the food a thin paste.
Third, the saliva changes some of the starch to sugar. Starch must be all changed to sugar before it can feed the cells.