Nutrients are naturally occurring chemical substances found in food. Proteins contain amino acids, sometimes referred to as the building blocks of protein. Dietary protein is supplied from plant and animal sources. Proteins are needed to build and repair body tissue and for the metabolic functions of our bodies. Lipids include fats and oils from plants and animals.
Cholesterol is a fat found only in animal products.
Lipids are of special interest because they are linked to the development of heart disease, the leading cause of death among Americans. The carbohydrates in our diet come from plant foods. Simple carbohydrates include the different forms of sugar, while complex carbohydrates include starches and dietary fiber. Minerals , also needed only in small amounts, have many different functions. Some minerals assist in the body's chemical reactions and others help form body structures.