Copper is an essential trace element present in the diet and in the human body. It is
needed to absorb and utilize iron. It is also
part of the antioxidantenzyme, superoxide dismutase (SOD). Copper is needed
to make adenosine triphosphate (ATP), the energy the body runs on. Synthesis of some hormones
requires copper, as does the synthesis of collagen (the "glue" that holds connective tissue
together). In addition, the enzyme, tyrosinase, which plays a role in the production of skin
pigment, requires copper to function.
Copper has been used in
connection with the following conditions (refer to the individual
health concern for complete information):
Who is likely to be deficient?
Many people consume slightly less than the “safe and adequate range” of copper,
1.5–3.0 mg per day. Little is known about the clinical effects of these marginally
adequate intakes, though frank copper deficiency is uncommon. Children with Menkes’ disease are unable to absorb copper
normally and become severely deficient unless medically treated early in life. Deficiency can
also occur in people who supplement with zinc without also increasing copper intake. Zinc interferes with copper absorption.1
Health consequences of zinc-induced copper deficiency can be quite serious.2 In the
absence of copper supplementation, vitamin C
supplementation has also been reported to mildly impair copper metabolism.3 Copper
deficiency can result in anemia, lower levels of HDL (“good”) cholesterol, or cardiac arrhythmias.
How much is usually taken?
Most people consume less than the recommended amount of this mineral. Some doctors
recommend supplementing the average diet with 1–3 mg of copper per day. While the
necessity of supplementing a normal diet with copper has not been proven, most people who take
zinc supplements, including the zinc found in
multivitamin-mineral supplements, should
probably take additional copper.
Cupric oxide (CuO) is a form of copper frequently used in vitamin-mineral supplements sold
over-the-counter. However, animal studies have shown conclusively this form of copper is
poorly absorbed from the gut; it should therefore not be used in supplements.4
5 6 7 Several other forms of copper (including copper
sulfate, cupric acetate, and alkaline copper carbonate) are better absorbed, and are therefore
preferable to cupric oxide.8
Are there any side effects or interactions?
The level at which copper causes problems is unclear. But in combination with zinc, up to 3 mg per day is considered safe. People
drinking tap water from new copper pipes should consult their doctor before supplementing,
since they might be getting enough (or even too much) copper from their water. People with Wilson’s disease should never take
copper.
Zinc interferes with copper absorption. People taking zinc supplements for more than a few
weeks should also take copper (unless they have Wilson’s disease). In the absence of
copper supplementation, vitamin C may
interfere with copper metabolism. Copper improves absorption and utilization of iron.
Preliminary evidence shows that the levels of copper in the blood were higher among people
who died from coronary heart disease than
among those who did not.9 However, animals studies and some human studies suggest
that, if anything, copper may prevent the development of heart disease. Although it is not
clear why people who died of heart disease had elevated copper levels, this finding could be
due to chronic inflammation, which is known to be associated with increased copper
levels.10
Are there any drug
interactions?
Certain medicines may interact with copper. Refer to drug interactions for a list of those medicines.
References:1. Sandstead HH. Requirements and toxicity of essential trace elements,
illustrated by zinc and copper. Am J Clin Nutr 1995;61(suppl):62S–4S.
2. Broun ER. Greist A, Tricot G, Hoffman R. Excessive zinc ingestion. A
reversible cause of sideroblastic anemia and bone marrow depression. JAMA
1990;264:1441–3.
3. Jacob RA, Skala JH, Omaye ST, Turnlund JR. Effect of varying ascorbic
acid intakes on copper absorption and ceruloplasmin levels of young men. J Nutr
1987;117:2109–15.
4. Aoyogi S, Baker DH. Bioavailability of copper in analytical-grade and
feed-grade inorganic copper sources when fed to provide copper at levels below the chicks
requirement. Poult Sci 1993;72:1075–83.
5. Baker DH, Odle J, Funk MA, Wieland TM. Bioavailability of copper in
cupric oxide, cuprous oxide and in a copper-lysine complex. Poult Sci
1991;70:177–9.
6. Cromwell GL, Stahly TS, Moneque HJ. Effects of source and level of
copper on performance and liver copper stores in weanling pigs. J Anim Sci
1989;67:2996–3002.
7. Ledoux DR, Henry PR, Ammerman CB, et al. Estimation of the relative
bioavailability of inorganic copper sources for chicks using tissue uptake of copper. J
Anim Sci 1991;69:215–22.
8. Baker DH. Cupric oxide should not be used as a copper supplement for
either animals or humans. J Nutr 1999;129:2278–9.
9. Ford ES. Serum copper concentration and coronary heart disease among
US adults. Am J Epidemiol 2000;151:1182–8.
10. Youssef A, Wood B, Baron DN. Serum copper: a marker of disease
activity in rheumatoid arthritis. J Clin Pathol 1983;36:14–17.