All food is built up in nature's laboratory by a process called synthesis; For example, take the apple which is made up chiefly of fruit sugar and cellulose with accompanying vitamines, salts, and water. The sugar and cellulose both belonging to the carbohydrate class contain the chemical elements carbon, hydrogen, and oxygen.

The chlorophyll, or green coloring matter of the plant first manufactures starch, obtaining its carbon from the ever present carbonic acid gas or carbon dioxid (CO2) of the air and giving back to the air the oxygen. Water (H1O), coming up through the roots with its hydrogen and oxygen, supplies to the chlorophyll these elements to complete the process of starch making.*

From some of this starch cellulose is made and later as the apple ripens the remaining starch is changed into sugar.

In the same way the elements necessary for the vitamines and salts are obtained from the soil. All are combined in a wonderful way until we have as a result the finished product, the apple ripened and tinted by the sun.

Before it can be utilized in the body, however, a very different process goes on. From the time the apple is seized by the teeth the process becomes one of disintegration or analysis, begun by the mechanical action of mastication. It is continued by the muscular activity of the digestive tract until the food becomes a thoroughly liquified mass.