Copper is an essential mineral that plays an important role in iron absorption and transport. It is considered a trace mineral because it is needed in very small amounts. Only 70–80 mg of copper are found in the body of a normal healthy person. Even though the body needs very little, copper is an important nutrient that holds many vital functions in the body.
Copper is essential for normal development of the body because it:
- Participates in a wide variety of important enzymatic reactions in the body.
- Is a component of or a cofactor for approximately 50 different enzymes. These enzymes need copper to function properly.
- Is essential for iron absorption and transport. Iron is needed to make hemoglobin, a main component of red blood cells. Therefore, copper deficiency is often linked to iron-deficiency anemia.
- Is required to build elastin and collagen, which are an important components of bones and connective tissues. Therefore, copper is believed to protect the bones and joints against degeneration and osteoporosis.
- Is required for melanin production. People with copper deficiency may have pale skin and hair.
- Is a key mineral for the immune system. Copper promotes wound healing. Studies show that premature infants or children with genetic copper defects are at high risk of getting infections and would significantly improve with copper supplementation.
- Attacks free radicals. Copper is a strong antioxidant. It works by attaching itself to the enzyme Superoxide dismutase (SOD). Copper also binds to a protein to form ceruloplasmin, which is an antioxidant.
- Helps the body produce energy. Copper participates in many oxidative reactions that break down fats in fat tissue to produce much needed energy. Copper deficiency has been associated with high cholesterol levels.
- Is necessary for normal functioning of insulin. Copper deficiency is also associated with poor blood glucose control.
- Is needed for normal functioning of the cardiovascular system.
- Protects the structure and function of the nervous system, including the brain. Copper protects nerve fiber by maintaining myelin, the insulating sheath that surrounds nerve cells. It also aids the transmission of nerve signals in the brains.
Copper supplements may be beneficial in treating or preventing copper deficiency. Copper deficiency used to be relatively rare because the body requires so little of it, only about 2 mg per day. In addition, it is available naturally in a variety of foods such as whole grains, shellfish, nuts, beans, and leafy vegetables. Additional sources of copper are the copper water pipes that run through homes or the copper cookware in the kitchen. These sources leach copper into the water we drink and the food we eat. The level of copper in drinking water is sometimes so high that it becomes a public concern. However, scientists now realize that copper deficiency, especially borderline cases, is more common than once thought. Copper deficiency is currently on the rise due to a decrease of whole foods in the diet and high consumption of fatty and processed foods.
It was discovered in 2001 that vegetarian diets generally contain more copper, but that the absorption efficiency was lower for lactoovo vegetarians than for nonvegetarians. The study also showed that the increased amounts of copper in the vegetarian diets allow for greater copper content.
Besides dietary causes, certain diseases or conditions may reduce copper absorption, transport or increase its requirements, resulting in abnormally low copper blood levels. Increased copper intake through diet or supplementation may be necessary in the following conditions:
- premature infants fed only cow's milk
- pregnant women
- celiac disease, sprue, cystic fibrosis, or short-bowel syndrome (these diseases cause poor absorption of dietary copper)
- kidney disease
- high consumption of zinc or iron (these minerals interfere with copper absorption)
- highly processed foods (copper is stripped away during food processing)
- Menkes syndrome (copper deficiency is caused by genetic defects of copper transport; Menkes syndrome patients cannot use copper supplied by the diet efficiently)
Symptoms of copper deficiency include:
- malnourished infants
- prominently dilated veins
- pale hair or skin
- poorly formed bones
- nervous system disorders
- high cholesterol levels
- heart disease
- loss of taste
- increased susceptibility to infections
- birth defects
Exceeding the daily requirement is dangerous, however, because copper toxicity commonly occurs. Copper toxicity is a very serious medical problem. Acute toxicity due to ingestion of too much supplement, for example, may cause nausea, vomiting, abdominal pain, diarrhea, dizziness, headache, and a metallic taste in the mouth.
Copper is a good antioxidant. It works together with an antioxidant enzyme, superoxide dismutase (SOD), to protect cell membranes from being destroyed by free radicals. Free radicals are any molecules that are missing one electron. Because this is an unbalanced and unstable state, a radical is desperately finding ways to complete its pair. Therefore, it reacts to any nearby molecules to either steal an electron or give away the unpaired one. In the process, free radicals initiate chain reactions that destroy cell structures. Like other antioxidants, copper scavenges or cleans up these highly reactive radicals and changes them into inactive, less harmful compounds. Therefore, it can help prevent cancer. In 2001, a study reported that concentrations of copper sulfate and ascorbate may inhibit breast cancer growth. With further study, the combination may even prove useful as a chemotherapy agent for certain breast cancer patients.
Copper may play a role in preventing osteoporosis. Calcium and vitamin D have long been considered the mainstay of osteoporosis treatment and prevention. However, a recent study has shown that they can be even more effective in increasing bone density and preventing osteoporosis if they are used in combination with copper and two other trace minerals, zinc and manganese.
Copper has been a folklore remedy for rheumatoid arthritis since 1500 B.C. in ancient Egypt. Some people believe that wearing jewelry made of copper may relieve arthritic symptoms. To evaluate the effect of copper for the treatment of rheumatoid arthritis, Dr. Walker and his colleagues conducted a study of 77 arthritic patients. Patients were divided into two groups: treatment group wearing copper jewelry and placebo group wearing nothing or aluminum jewelry. In this study, patients who wore copper bracelets felt significantly better than those in the placebo group. In addition, patients in the treatment group reported recurrences of symptoms after the bracelets were removed. To explain the effects of the copper bracelets, these researchers suggested that copper contained in the bracelets was dissolved in sweat and then absorbed through the skin. They suspected that copper's effectiveness may be related to its role as an antioxidant. They also believe that copper may function as both an anti-inflammatory agent and as an antioxidant. Thus, it is possibly effective in reducing inflammatory response to such conditions as rheumatoid arthritis.
Copper is contained in many multivitamin/mineral preparations. It is also available as a single ingredient in the form of tablets. These tablets should be swallowed whole with a cup of water, preferably with meals, to avoid stomach upset. A person may choose any of the following preparations: copper gluconate, copper sulfate, or copper citrate. However, copper gluconate may be the least irritating to the stomach.
Zinc and copper compete with each other for absorption in the gastrointestinal tract. As a result, excessive copper intake may cause zinc deficiency, and vice versa. Therefore, a person should take zinc and copper supplements together in ratios of 10:1 or 15:1.
Those adding copper supplements to their diets should consider:
- Informing their doctors for proper instruction and monitoring of side effects. Copper toxicity due to excessive doses of copper supplements has been reported.
- Although there currently is no recommended daily allowance (RDA) established for copper, 2 mg of copper per day is considered sufficient and safe. Nausea and vomiting may occur in persons taking more than 20 mg of copper daily.
- It is not known if copper supplementation may harm a growing fetus. However, as with any drugs, pregnant or nursing women should not take copper or any other supplements or drugs without first consulting their doctors.
- In certain areas, drinking water may contain high levels of copper. Periodic checks of copper levels in drinking water may be necessary.
- Because individual antioxidants often work together as a team to defend the body against free radicals, the balance between copper, zinc, and iron must be maintained. Excessive intake of one nutrient might result in a deficiency of other minerals and decreased resistance to infections and increased risk of heart disease, diabetes, arthritis, and other diseases.
A person should stop taking copper supplements and seek medical help immediately if having the following signs or symptoms:
- abdominal pain
Factors that increase copper concentrations
Certain disorders have been known to increase copper levels. Persons with these conditions should not take copper supplements as they may cause copper toxicity.
- recent heart attacks
- lupus erythematosus
- cirrhosis of the liver
- leukemia and some other forms of cancer
- viral infections
- ulcerative colitis (This inflammatory bowel disease may cause accumulation of copper in the body. Excessive amount of copper may worsen many symptoms of this disease by increasing susceptibility to infections and inhibiting wound healing.)
- Wilson's disease (This disease causes accumulation of copper in the tissues. As a result, patients have liver disease, mental retardation, tremor and poor muscle coordination. They also have copper deposits in the cornea of the eye. To manage this disease, patients are put on a low-copper diet and given penicillamine, a drug that attaches itself to copper and increases its excretion.)
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Teresa G. Odle