Copper plays a role in making red blood cells and maintaining nerve cells and the immune system.
Copper also helps the body form collagen and absorb iron, and plays a role in energy production. Most copper in the body is found in the liver, brain, heart, kidneys, and skeletal muscle. Both too much and too little copper can affect how the brain works. The recommended daily allowance (RDA) is around 900 micrograms a day for adolescents and adults. The upper limit for adults aged 19 years and above is 10 milligrams (mg) a day. An intake above this level could be toxic. Both copper deficiency and copper toxicity are rare in the United States (U.S).