Copper is a trace element that is essential for most animals, including humans. It is needed to absorb and utilise iron. The influence of copper upon health is due to the fact that it is part of enzymes, which are proteins that help biochemical reactions occur in all cells. Copper is involved in the absorption, storage, and metabolism of iron. The symptoms of a copper deficiency are similar to iron-deficiency anemia. Copper may be absorbed by both the stomach and small-intestinal mucosa, with most absorbed by the small intestine. Copper is found in the blood bound to proteins.