Copper is a mineral stored primarily in the liver, with small amounts in all tissues in the body. Although only a small amount is needed, copper is an essential nutrient that plays a role in the production of hemoglobin (the main iron component of red blood cells), myelin (the substance that surrounds nerve fibers), collagen (a key component of bones and connective tissue), and melanin (a dark pigment that colors the hair and skin). Copper also works with vitamin C to help make a component of connective tissue known as elastin.

Copper can act as both an antioxidant and a pro-oxidant. As an antioxidant, it scavenges damaging particles in the body known as free radicals. Free radicals occur naturally in the body and can damage cell walls, interact with genetic material, and possibly contribute to the aging process as well as the development of a number of health conditions. Antioxidants can neutralize free radicals and may reduce or even help prevent some of the damage they cause.

When copper acts as a pro-oxidant at times, it promotes free radical damage and may contribute to the development of Alzheimer's disease and, possibly, cervical dysplasia (precancerous lesions of the cervix which forms the opening to the uterus). Maintaining the proper dietary balance of copper (along with other minerals such as zinc and manganese) is important. Your doctor or dietitian can help you do this.

Signs of possible copper deficiency include anemia, low body temperature, bone fractures and osteoporosis, low white blood cell count (the cells that help fight infection), irregular heartbeat, loss of pigment from the skin, and thyroid disorders. Gastrointestinal disease or surgery is a common cause of copper deficiency. Infants who do not have enough of this mineral tend to have poor feeding habits and lack proper growth.

Foods that contain copper include oysters, organ meats (especially liver), whole grain breads and cereals, shellfish, dark green leafy vegetables, dried legumes, nuts, and chocolate.

Anemia

Copper supplementation may be beneficial for individuals with anemia (a condition characterized by low hemoglobin levels) because this mineral works together with iron to form hemoglobin.

Arthritis

Animal studies suggest that oral copper supplements reduce the development and progression of arthritis. Many people with arthritis (both rheumatoid and osteo) apply copper solutions to their skin or wear copper bracelets in hopes of relieving pain and inflammation associated with this joint condition. Reports of success with these methods are mixed, but one clinical study from the 1970s found that copper bracelets worked better than placebo bracelets. Sweat can interfere with how well the topical copper solutions and bracelets work.

Burns

When skin is burned, a substantial percentage of micronutrients, such as copper, selenium, and zinc may be lost. This increases the risk for infection, slows the healing process, prolongs the hospital stay, and even increases the risk of death. However, people with major burns tend to lose copper more rapidly than other minerals. Although it is unclear which micronutrients are most beneficial for people with burns, many clinical studies suggest that a multivitamin including copper and other minerals may aid in the recovery process.

Inflammatory bowel disease (IBD)

People with the inflammatory bowel diseases (IBD), ulcerative colitis, and Crohn's disease cannot absorb essential vitamins and minerals, such as copper, as well as healthy individuals. When treating IBD, clinicians often recommend a multivitamin containing essential minerals.

In addition, inflammatory bowel disease may be related to oxidation or damage caused by free radicals. In fact, copper levels may be low in the inflamed tissue of those with IBD, particularly Crohn's disease.

Finally, a laboratory animal study found that copper-deficient rats tend to have elevated blood sugar levels over time, indicating a possible connection between low copper and diabetes. A clinical study including people with diabetes, however, found very different results. Copper levels were higher in people with diabetes compared to those without. In fact, the higher the copper level, the more likely the person was to have complications from diabetes, including retinopathy (damage to the retina of the eye), high blood pressure, or vascular disease.

Wound healing

Copper plays a major role in wound healing. Scientists think that introducing copper into wound dressings would not only reduce the risk of wound and dressing contamination, but also stimulate faster healing. Releasing copper from the dressings directly onto the wound promotes skin regeneration.

Others

One clinical study that followed over 1,600 patients with lung cancer found that dietary zinc and copper intakes are associated with reduced risk of lung cancer. Preliminary studies show that copper may inactivate HIV infectivity.

Among the best dietary sources of copper are:

• Seafood (such as oysters, squid, lobster, mussels, crab, and clams)
• Organ meats (such as beef liver, kidneys, and heart)
• Nuts and nut butters (such as cashews, filberts, macadamia nuts, pecans, almonds, and pistachios)
• Legumes (such as soybeans, lentils, navy beans, and peanuts)
• Chocolate (such as unsweetened or semisweet baker's chocolate and cocoa)
• Enriched cereals (such as bran flakes, shredded wheat, and raisin bran)
• Fruits and vegetables (such as dried fruits, mushrooms, tomatoes, potatoes, sweet potatoes, bananas, grapes, and avocado)
• Blackstrap molasses
• Black pepper

Multivitamins that include minerals generally provide copper. But, copper is also available as an individual oral supplement. Copper can also be found as a healing bracelet, topical gel, and in topical solutions.

The best way to get enough copper is through your diet. Proper absorption and metabolism of copper requires an appropriate balance with the minerals zinc and manganese. The following lists provide the recommended daily dietary intake of copper for children and adults from the Dietary Guidelines for Americans 2005, part of the U.S. Department of Health and Human Services.

Pediatric

For infants from birth - 6 months: The recommended daily intake is 200 mcg.

For infants 7 - 12 months: The recommended daily intake is 220 mcg.

For children 1 - 3 years: The recommended daily intake is 340 mcg.

For children 4 - 8 years: The recommended daily intake is 440 mcg.

For children 9 - 13 years: The recommended daily intake is 700 mcg.

For children 14 - 18 years: The recommended daily intake is 890 mcg.

Copper for children should be obtained from foods. Copper supplements should not be given to children.

Adult

For adults 19 years and older: The recommended daily intake is 900 mcg.

For pregnant females: The recommended daily intake is 1,000 mcg.

For breastfeeding females: The recommended daily intake is 1,300 mcg.

Adults taking copper supplements should also take zinc supplements (8 - 15 mg of zinc for every 1 mg of copper) as an imbalance of these two minerals can cause other health conditions.

Because of the potential for side effects and interactions with medications, you should take dietary supplements only under the supervision of a knowledgeable health care provider.

Excessive copper intake can cause nausea, vomiting, stomach pain, headache, dizziness, weakness, diarrhea, and a metallic taste in the mouth. Copper toxicity is rare but can cause heart problems, jaundice, coma, and even death. Do not use copper supplements if diarrhea is present. Water containing copper concentrations greater than 6 mg/L is associated with gastrointestinal symptoms (nausea and vomiting). If you have well water, it may be important to get the water tested for mineral content.

Copper toxicity may occur from using copper cookware and from water supplied by copper pipes on a regular basis. Copper can leach out of pipes into water, especially hot water, if it sits in copper pipes for an extended period of time. It is best to always cook with cold water. Flushing the system by running cold water for 2 - 3 minutes is an effective way to reduce copper. Also, it is best to avoid unlined copper cookware since copper can leach into acidic foods, such as vinegar, tomato, or citrus. If you have blue-green stains around your faucet or sink, or if you detect a metallic taste to your water, you may want to have your water tested by a certified laboratory.

Children and individuals with Wilson's disease, a hereditary syndrome that results in an accumulation of copper in the brain, liver, kidneys, and eyes, should not take copper supplements. Because high intakes of zinc and iron can impair absorption of copper, zinc has been used to decrease copper in people suffering from of Wilson's disease.

If you are currently being treated with any of the following medications, you should not use copper supplements without first talking to your health care provider.

Birth control medications and estrogen following menopause -- Birth control medications and estrogen replacement for post-menopausal women can increase blood levels of copper. Therefore, copper supplements are not appropriate and may be cause for concern in individuals taking either of these medications.

Nonsteroidal anti-inflammatory drugs (NSAIDs) -- Copper binds to NSAIDs (such as ibuprofen and naproxen) and appears to enhance their anti-inflammatory activity.

Penicillamine -- Penicillamine (a medication used to treat Wilson's disease and rheumatoid arthritis) reduces copper levels that may be the intended use, as in the case of Wilson's disease.

Allopurinol -- Test tube studies suggest that allopurinol (Zyloprim), a medication used to treat gout, may reduce copper levels.

Cimetidine -- Animal studies show that cimetidine (Tagamet), a medication used to treat ulcers and gastric esophageal reflux disease (when acid from the stomach enters the esophagus and causes heartburn and indigestion), may elevate copper levels in the body leading to damage of the liver and other organs.

Nifedipine -- In a human study, a lower concentration of copper was found in red blood cells after use of nifedipine (Procardia or Adalat).

Zinc -- Several laboratory and human studies have found that high levels of supplemental zinc taken over extended periods of time may result in decreased copper absorption in the intestines and copper deficiency. However, some studies in humans suggest that high dietary zinc may not interfere with the actual tissue or plasma concentrations of copper. Ask your health care provider if you need zinc and copper supplementation.

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