Our bodies are built up from the food we eat. There is a constant breaking down of the tissues of the body; every movement of every organ involves waste, and this waste is repaired from our food. Each organ of the body requires its share of nutrition. The brain must be supplied with its portion; the bones, muscles, and nerves demand theirs. It is a wonderful process that transforms the food into blood and uses this blood to build up the varied parts of the body; but this process is going on continually, supplying with life and strength each nerve, muscle, and tissue.