Whatever is not absorbed in the small intestines moves on to the large intestines to be eliminated. This is largely fiber and hard starches. It is converted into feces.

The next part that comes into play is about the human nutrition. According to his definition the author says nutrition is the study of the relationship between food and health. A nutrient is a substance, contained in food, that does at least one of three things:

- Provides energy.

- Provides a structural building block for the body.

- Helps regulate a process in the body.

There are six different classes of nutrients which are required for the proper growth and development of the body. These are,

1) Water

2) Minerals

3) Vitamins

4) Proteins

5) Carbohydrates

6) Lipids