Copper

Most of the copper in the body is located in the liver, bones, and muscle, but traces of copper occur in all tissues of the body. The liver excretes excess copper into the bile for elimination from the body. Copper is a component of many enzymes. Some of these enzymes are necessary for energy production or for the formation of the hormone epinephrine, red blood cells, bone, or connective tissue (which binds other tissues and organs together). Other enzymes act as antioxidants. They help protect cells against damage by free radicals, which are reactive by-products of normal cell activity.

See the sidebar Wilson's Disease: When Copper Accumulates.

Copper Deficiency

Copper deficiency is rare among healthy people. It occurs most commonly among infants who are premature, who are recovering from severe undernutrition, or who have persistent diarrhea. A severe disorder that impairs absorption of nutrients (such as celiac disease, Crohn's disease, cystic fibrosis, or tropical sprue) may cause this deficiency. A high intake of zinc or iron can decrease the absorption of copper.

Symptoms of copper deficiency include fatigue, bleeding under the skin, damage to blood vessels, and an enlarged heart. Anemia is common, and the number of white blood cells is decreased.

The diagnosis of copper deficiency is based on symptoms and on blood tests that detect low levels of copper and ceruloplasmin (a protein that contains copper). Copper deficiency is treated with a copper supplement.

Copper Excess

Excess consumption of copper is rare. Any copper not bound to a protein is toxic. Acidic food or beverages in prolonged contact with copper vessels, tubing, or valves can be contaminated with small amounts of unbound copper. Consuming even relatively small amounts of unbound copper may cause nausea, vomiting, and diarrhea. Large amounts can damage the kidneys, inhibit urine production, and cause anemia due to the rupture of red blood cells (hemolysis) and even death.

The diagnosis is made by measuring copper and ceruloplasmin levels in the blood or urine. Treatment involves use of drugs that bind with copper.