Copper deficiency is commonly found together with iron deficiency, especially with iron deficiency anemia. Fatigue, paleness, skin sores, and edema may appear with this, as may slowed growth, hair loss, anorexia, diarrhea, and dermatitis. High zinc levels or intake can lead to lower copper levels and some symptoms of copper deficiency. The reduced red blood cell function and shortened red cell life span can influence energy levels and cause weakness and labored respiration from decreased oxygen delivery. Low copper levels may also affect collagen formation and thus tissue health and healing. Reduced thyroid function, weakened immunity, cardiovascular disease, increased cholesterol, skeletal defects related to bone demineralization, and poor nerve conductivity, including irregular heart rhythms, might all result from copper depletions. Copper deficiency results in several abnormalities of the immune system, such as reduced cellular immune response, reduced activity of white blood cells, and, possibly, reduced thymus hormone production, all of which may contribute to an increased infection rate. Infants fed an all-dairy (cow's milk) diet without copper supplements may develop copper deficiency. Some children with iron deficiency show reduced levels of copper as well. It is also likely that during pregnancy copper will be deficient unless supplemented with at least 2 mg. daily.

Requirements: The RDA for copper in adults is 2 mg. (liberally, 2-3 mg.) per day. For children it is 1-2 mg. and for infants about 0.5-1 mg. The average adult intake had been estimated at 2.5-5 mg. per day, although recent reports suggest lower levels.

Many nutritionists do not supplement copper at all or at least not more than 2 mg. per day in a general supplement because of the concern about toxicity and because excess copper can interfere with absorption of zinc. Zinc deficiency can cause a great number of problems, such as hair loss, menstrual problems, and weakened immunity. If the soil in which our food is grown is known to be high in copper or if we drink water from copper pipes, we should probably avoid copper supplements. If we eat a diet that includes whole grains, nuts, and leafy green vegetables or eat much liver, we are probably obtaining sufficient levels from our diet. Overall, if we do supplement zinc, we should also take copper in a ratio of 15-30 mg. zinc to 2 mg. copper, unless of course, we are trying to reduce copper or correct a zinc deficiency. Likewise, if we take copper we should add zinc, unless we are treating high zinc levels or copper deficiency.