Copper
Copper is a trace mineral that is essential for human health. It works with enzymes, which are proteins that aid in the biochemical reactions of every cell. Copper assists these enzymes in many crucial reactions in the body.
Functions
Copper’s functions include:
- Assisting in energy production
- Protecting cells from free radical damage
- Helping lysyl oxidase, an enzyme that strengthens connective tissue
- Assisting the brain neurotransmitters, norepinephrine, and dopamine
- Helping your body make hemoglobin, which is needed to carry oxygen to red blood cells
- Keeping the immune system, bones, blood vessels, and nerves healthy
Recommended Intake
Age Group |
Recommended Dietary Allowance/Adequate Intake
(milligrams/day) |
Upper Limit
(milligrams/day) |
---|---|---|
0-6 months | 0.20* | Not determinable |
7-12 months | 0.22* | Not determinable |
1-3 years | 0.34 | 1.0 |
4-8 years | 0.44 | 3.0 |
9-13 years | 0.70 | 5.0 |
14-18 years | 0.89 | 8.0 |
19 years and older | 0.90 | 10.0 |
Pregnancy
18 years and younger | 1.00 | 8.00 |
Pregnancy
over 18 years | 1.00 | 10.0 |
Lactation
18 years and younger | 1.30 | 8.00 |
Lactation
over 18 years | 1.30 | 10.0 |
*Adequate intakes
Copper Deficiency
Many studies show that Americans consume less than adequate amounts of dietary copper. However, copper deficiency in adults is rare. A deficiency may occur, though, due to certain genetic problems, long-term shortages of dietary copper, or excessive intakes of zinc, iron, or antacids. In addition, the following conditions may increase your need for copper:
- Burns
- Diarrhea
- Intestinal disease
- Kidney disease
- Disease of the pancreas
- Stomach removal
- Long-term stress
Symptoms of copper deficiency include anemia , bone loss , a decrease in certain white blood cells, loss of hair color, and pale skin. A lifetime of marginal dietary copper could possibly lead to heart disease. Premature infants and infants suffering from malnutrition may have deficiencies of copper.
If you are unable to meet your copper needs through dietary sources, copper supplements may be necessary. Copper supplements are usually taken by mouth, but in some cases are given by injection. Your doctor should determine if you need such supplementation.
Copper Toxicity
Cases of toxicity from copper are rare.
Excess copper intake may lead to liver damage. Doses of 10 mg/day may lead to weakness and nausea. Symptoms of copper toxicity may include:
Major Food Sources
Foods high in copper include organ meats (liver, heart, kidney, brain), seafood, nuts, seeds, wheat bran, cereals, whole grain products, and cocoa products. Although these foods are rich in copper, the amount of copper you absorb may be influenced by other dietary components. For example, excessive dietary intakes of iron or zinc may decrease copper absorption. Vitamin C supplementation has also been found to decrease copper absorption.
Food | Serving Size |
Copper Content
(milligrams) |
---|---|---|
Nuts | 1 tablespoon (28 g) | 0.2 to 0.5 mg |
Oysters, raw | 4-5 ounces | 1.0 to 3.7 mg |
Liver, raw | 4-5 ounces | 3.8 mg |
Legumes, cooked | 1/3 cup | 0.2 mg |
Turkey—dark meat, cooked | 3 ounces | 0.1 to 0.2 mg |
Whole wheat bread | 1 slice | 0.1 to 0.2 mg |
Dark chocolate | 3 ounces | 0.75 mg |
Health Implications
If you have a medical condition that impairs your body’s ability to absorb, use, and excrete copper, your doctor may recommend reducing your dietary intake of copper. Such conditions may include:
- Wilson’s disease —a genetic disease in which the body cannot excrete copper
- Hemodialysis for kidney failure with a dialysis solution contaminated with excess copper
- Liver disease
If you are taking copper supplements, it is important that you let your doctor know if you have the conditions listed above, or if you are taking any of the following:
- Penicillamine
- Trientine
- Zinc supplements (taken by mouth)
- Copper intrauterine device (IUD)
Another genetic disease, Menkes syndrome , prevents copper absorption in the intestine and produces symptoms of copper deficiency.
Tips for Lowering Copper Intake
If your doctor recommends that you lower your dietary intake of copper, you should reduce your intake of the following foods:
- Lamb and pork
- Quail, duck, and goose
- Squid, salmon
-
Shellfish, such as:
- Oysters
- Scallops
- Shrimp
- Lobster
- Clams
- Crab
- Organ meats: liver, heart, kidney, brain
- Soy protein products, including tofu
- All nuts and seeds
-
Dried beans, such as:
- Soybeans
- Lima beans
- Baked beans
- Garbanzo beans
- Pinto beans
- Peas
- Lentils
RESOURCES:
American Dietetic Association
http://www.eatright.org/
Food and Nutrition Information Center
US Department of Agriculture
http://www.nal.usda.gov/fnic
CANADIAN RESOURCES:
Dietitians of Canada
http://www.dietitians.ca/
Health Canada
http://www.hc-sc.gc.ca/index_e.html/
References:
American Society for Nutritional Sciences website. Available at: http://www.nutrition.org
National Academy of Sciences website. Available at: http://www.nationalacademies.org/
National Institutes of Health website. Available at: http://www.nih.gov/
US Department of Agriculture. Food and Nutrition Information Center website. Available at: http://www.nal.usda.gov/fnic
Last reviewed January 2009 by Jill D. Landis, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.
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