Copper (Cu)
Copper is an essential trace element. An adult contains around 100-150 micrograms of copper. Most of it is found in the liver, brain, kidneys, and heart. Fetuses and newborn babies have particularly high copper levels in their liver. In fact, the liver is believed to serve as an extra storage facility during lactation where the copper content in breastmilk is rather low.
Functions and importance for
- Pigmentation in skin and hair
- Building of connective tissue, bones, and cartilage
- Synthesis of the stress hormone adrenalin
- Nervous system
- Synthesis of the signaling substances noradrenalin and dopamine
- Red blood cells (by binding iron to oxygen-carrying hemoglobin)
- Antioxidant that counteracts cell damage caused by free radicals
Deficiencies and poor utilisation may be caused by
- Extreme slimming programmes
- High-dosage supplements of vitamin C and iron that may inhibit the uptake of copper
- Large supplements of zinc over longer periods of time, as this may inhibit the uptake of copper
- Celiac disease (gluten allergy)
- Penicillamine (against rheumatoid arthritis)
Deficiency symptoms
Rarely seen but may result in:
- Increased tendency towards infections and poisonings
- Anemia
- Elevated cholesterol levels
- Heart rhythm disturbances
- Lack of skin and hair pigmentation
- Bone changes and osteoporosis
- Menkes disease (hereditary deficiency disease)
- Caused by impaired copper absorption from the gastrointestinal tract. The following may occur:
- The above listed deficiency symptoms
- Changes in the nervous system
- Low blood pressure and low body temperature
- Shortness of breath
- Mental retardation
Sources
Most foods that contain iron also contain copper. The best sources are liver and organ meat, meat, nuts, whole-grain products, shellfish, beans, and dark chocolate.
Copper content in mg per 100 grams
| Raw oysters | 8 |
| Beef liver | 5 |
| Walnuts and almonds | 1 |
| Brown beans | 0.5 |
Recommended daily allowance (RDA)
It is not known exactly how much copper the human body needs, but the RDA is as follows:
Adults: 11 years of age and older: 1 mg
Children: 1-10 years of age: 0.34 mg
Increased need
Rarely seen. Supplements are only recommended if a copper deficiency has been detected.
Adults: Max. 3 mg daily
Children: Max. 1 mg daily.
Overdosing - side effects
Copper is toxic in large quantities and may cause:
- Irritation of the intestinal mucosa
- Nausea, vomiting, and diarrhea
- Zinc deficiency
- A situation where copper no longer functions as an antioxidant bus as a pro-oxidant with potentially harmful effects
Large doses of several grams may cause:
- Anemia
- Liver damage
- Low blood pressure
- Possibly death
Wilson's syndrome (hereditary disease with copper overload)
A result of morbid copper metabolism. Only develops in individuals where both parents are genetically predisposed. The disease is treated with copper-depleted diet and penicillamine that binds copper and prevents the uptake of the nutrient. Left untreated, this disease may cause death and it is known to lead to:
- Copper accumulation (especially in the liver)
- Chronic hepatitis
- Liver cirrhosis
- Anemia
- Mental retardation
Important information
The body's supply of copper must be in balance with the zinc supply at all times.
Drinking water that is contaminated with copper from water pipes may cause diarrhea - especially in newborn babies and infants.
Water from the hot faucet absorbs copper from the water pipes more easily than cold water. For that reason, it is advised only to drink water from the cold faucet and, if possible, to allow the water to run for a while before drinking it. This is particularly relevant in situations where the faucet has not been in use for some time.
Avoid food getting in contact with copper from non-galvanized pots and cooking utensils. Copper is particularly likely to be released from these items when they get in contact with acid-containing things like vinegar, lemon, and wine.
Contraceptive pills and estrogen therapy after menopause may increase the content of copper in blood. NSAID preparations (used to treat rheumatism and pain) may enhance the effect of copper.
The colouring agent E141 that adds bluish green/bluish black colours contains copper.