Copper is essential to all living organisms as a trace dietary mineral because it is a key constituent of the respiratory enzyme complex - cytochrome C oxidase.
Copper is a minor mineral, a transition element, qualified in nutrition as a trace element due to its low quantitative importance (<10 mg/ kg of body weight). Most of the body’s copper is stored in the liver. It can be toxic in excessive quantities, as produced by some predisposed breeds or lines of dog.
Copper proteins have diverse roles in biological electron transport and oxygen transportation. Cytochrome C oxidase is required for aerobic respiration. Copper is also incorporated into superoxide dismutases which are important for destroying free radicals.
Food sources high in copper include shell-fish, whole grains, beans, nuts, potatoes, meat organs (liver and kidneys).