Copper: Roles, Food Sources, Deficiency and Excess
Copper's role with iron and blood cells, food sources, intake figures by country, deficiency (often linked to excess zinc), upper limits, Wilson disease and safety cautions.
Content last updated . This page has not been medically reviewed.
What is Copper good for?
What the body uses it for, and how strong the evidence is. A normal job in the body is not proof that extra supplements add benefit; each card says which.
Red blood cell formation and iron use
Established roleCopper works with iron to help the body make red blood cells and form haemoglobin, which carries oxygen.
Supplements: Supplements correct a copper deficiency; no good evidence of extra benefit when intake is adequate.
White blood cell production
Established roleCopper helps the body make white blood cells, part of the immune system.
Supplements: Supplements correct a copper deficiency; no good evidence of extra benefit when intake is adequate.
Iron absorption and handling
Established roleCopper aids how the body absorbs and uses iron.
Supplements: Supplements correct a copper deficiency; no good evidence of extra benefit when intake is adequate.
Healthy blood vessels
Established roleCopper helps keep blood vessels healthy.
Supplements: No evidence was read that supplements improve blood vessel health when copper is adequate.
Nerve health
Established roleCopper helps keep nerves healthy, and a lack can affect the nervous system.
Supplements: Supplements correct a copper deficiency; no good evidence of extra benefit when intake is adequate.
Bone health
Established roleCopper helps keep bones strong, and low copper may lead to osteoporosis.
Supplements: No evidence was read that extra copper strengthens bones when intake is adequate.
Infant growth and brain development
Established roleCopper is thought to matter for growth and brain development in infants.
Supplements: Not tested as a supplement benefit in the sources read; a varied diet is said to supply enough.
Immune function
Established roleCopper supports immune function as part of normal body chemistry.
Supplements: Supplements correct a copper deficiency; no good evidence of extra benefit when intake is adequate.
Connected topics
Open a group to see how each topic connects and how strong the evidence is.
Health goals (2)
- Bone HealthEstablished role
Copper helps keep bones healthy and low intake may lead to osteoporosis. No evidence was read that extra copper builds bone in people with enough.
- Immune SupportEstablished role
Copper helps make white blood cells, but supplements are not shown to improve immunity when intake is adequate.
Body systems (11)
- Hepatic / Liver SystemDocumented risk
Long-term high doses of copper can damage the liver. In Wilson disease, an inherited disorder, copper builds up in the liver.
- Immune SupportEstablished role
Copper takes part in making white blood cells. This is a normal role, not proof that extra copper strengthens immunity.
- Immune SystemEstablished role
Copper helps the body make white blood cells and supports immune function. Supplements are not shown to boost immunity when intake is adequate.
- Liver & DetoxDocumented risk
Long-term high copper intake can damage the liver, and people with Wilson disease should not take multivitamins containing copper.
- Nervous SystemEstablished role
Copper helps keep nerves healthy, and low copper can affect the nervous system. Extra copper has not been shown to help people who already get enough.
- Bones, Joints & MusclesEstablished role
Copper helps keep bones healthy, and low intake may lead to osteoporosis. No evidence was read that extra copper helps joints or muscles.
- Cardiovascular SystemEstablished role
Copper helps keep blood vessels healthy and works with iron to form red blood cells. Supplements are not shown to benefit people with adequate copper.
- Heart & CirculationEstablished role
Copper helps keep blood vessels healthy, and it is needed to form haemoglobin, which carries oxygen. This does not show that supplements protect the heart.
- Kidney & UrinaryDocumented risk
Long-term high doses of copper can damage the kidneys, according to the NHS.
- Musculoskeletal SystemEstablished role
Copper helps keep bones healthy, and low intake may lead to osteoporosis. Supplements mainly matter when copper is low.
- Urinary SystemDocumented risk
Long-term high doses of copper can damage the kidneys, according to the NHS.
Body parts (7)
- BrainDocumented risk
Copper is linked to brain development, and in Wilson disease extra copper can damage the brain. The brain-development role is described only as 'thought' to matter by the NHS.
- Immune SystemEstablished role
Copper helps the body make white blood cells and supports immune function.
- LiverDocumented risk
Long-term high doses of copper can damage the liver, and in Wilson disease copper builds up there.
- Nervous SystemEstablished role
Copper helps keep nerves healthy, and low copper can affect the nervous system.
- Blood VesselsEstablished role
MedlinePlus says copper helps keep blood vessels healthy. No evidence was read that supplements improve vessel health when copper is adequate.
- BonesEstablished role
Copper helps keep bones healthy, and low intake may lead to osteoporosis. A high zinc intake can lower copper absorption and weaken bones.
- KidneysDocumented risk
Long-term high doses of copper can damage the kidneys, and Wilson disease can affect the kidneys.
Functional actions (2)
- AntioxidantEstablished role
Copper is part of the body's own antioxidant defence. This does not mean copper supplements act as an antioxidant in people with adequate intake.
- Energy ProductionEstablished role
Copper is involved in cellular respiration, the way cells use oxygen to release energy. Extra copper has not been shown to raise energy in people who are not deficient.
Root causes (1)
- Nutrient DeficiencyDeficiency link
Too little copper can cause anaemia and other problems. It is uncommon in people who eat a varied diet, and high zinc intake is one known cause.
Habits (1)
- Balanced NutritionEstablished role
The NHS says a varied diet should supply all the copper needed, so supplements are usually unnecessary.
Biomarkers (1)
- HemoglobinDeficiency link
Copper is needed to form haemoglobin, and copper deficiency can cause anaemia. Anaemia has other causes too, such as low iron.
Conditions & symptoms (4)
- AnemiaDeficiency link
Too little copper can cause anaemia, which usually reverses with copper replacement over several weeks. Diagnosis and treatment need a clinician.
- Hepatolenticular DegenerationDocumented risk
A rare inherited disorder where the body cannot remove extra copper, which builds up in the liver, brain and other organs. People with it are told not to take multivitamins containing copper.
- Menkes Kinky Hair SyndromeDeficiency link
A very rare inherited disorder of copper handling present from before birth in male infants. It is not caused by diet.
- OsteoporosisDeficiency link
MedlinePlus says low copper may lead to osteoporosis; this is a deficiency link, not evidence that supplements treat osteoporosis.
Overview
Copper is an essential trace mineral. The NHS (UK) says it helps produce red and white blood cells and trigger the release of iron to form hemoglobin, and is thought to matter for infant growth, brain development, the immune system and strong bones. [1] MedlinePlus (US) says the body cannot make its own copper, so it must come from food, and that copper also aids iron absorption and helps keep blood vessels, nerves, the immune system and bones healthy. [2] The NHS says you should be able to get all the copper you need from a varied diet. [1]Labels used: established nutritional role / deficiency treatment, insufficient evidence, Proper evidence not found. For the zinc side of the balance see Zinc.
Food sources
The NHS lists nuts, shellfish and offal. [1] MedlinePlus lists oysters and other shellfish, whole grains, beans, nuts, potatoes and organ meats such as liver and kidneys, plus dark leafy greens, dried fruit such as prunes, cocoa, black pepper and yeast. [2] We did not read a food-composition table, so no per-serving amounts are given here; see Foods high in copper and manganese.Official intake levels
Figures differ by country. Amounts are copper, in milligrams (mg) or micrograms (mcg; 1,000 mcg = 1 mg).| Group | Level | Source and year |
|---|---|---|
| Adults 19 to 64 (UK) | 1.2 mg a day | NHS, page reviewed 2020 [1] |
| Adults 19 and over (US RDA) | 900 mcg a day | MedlinePlus, reviewed 2025 [2] |
| Teens 14 to 18 (US RDA) | 890 mcg a day | MedlinePlus [2] |
| Children 1 to 3 / 4 to 8 / 9 to 13 (US RDA) | 340 / 440 / 700 mcg a day | MedlinePlus [2] |
| Pregnancy / breastfeeding (US RDA) | 1,000 / 1,300 mcg a day | MedlinePlus [2] |
| Infants 0 to 6 / 7 to 12 months (US adequate intake) | 200 / 220 mcg a day | MedlinePlus [2] |
| Food, water and supplements together (UK) | 10 mg or less a day is unlikely to cause harm | NHS, 2020 [1] |
| Adults, tolerable upper level (EU) | 5 mg a day | EFSA overview v11, August 2025 (SCF 2003 value) [3] |
The UK and EU upper figures differ, so neither is universal. The EFSA table also notes that in 2023 its Scientific Committee set an acceptable daily intake of 0.07 mg per kg of body weight, a different kind of guidance. [3] The US upper limit could not be verified because the NIH Office of Dietary Supplements page was blocked when we tried to read it.
Deficiency
MedlinePlus says people normally get enough copper from food, and that a lack may lead to anemia and osteoporosis. It also describes Menkes disease, a very rare disorder of copper metabolism present before birth in male infants. [2] A 2018 review says copper deficiency affects bone marrow blood-cell production, optic nerve function and the nervous system, is diagnosed by measuring serum copper, ceruloplasmin and 24-hour urine copper, and is treated with copper replacement; blood effects were fully reversible over 4 to 12 weeks, while nerve effects were only partly reversible. [4] Deficiency needs a clinician's diagnosis and care, not self-treatment; see Copper deficiency.Zinc and copper
The NHS says high zinc doses reduce how much copper the body can absorb, which can lead to anemia and weaker bones. [1] A 2026 systematic review of 37 case reports of zinc-related blood problems found low serum copper in every patient, and recovery in most after zinc exposure stopped and copper was given. [5] The 2018 review notes copper and zinc share part of their absorption route. [4] Adding copper on your own to "balance" zinc is not something these sources advise; ask a clinician about testing. See Mineral interactions and absorption.Too much copper and Wilson disease
The NHS says high doses could cause stomach pain, sickness, diarrhea and, if taken for a long time, damage to the liver and kidneys. [1] MedlinePlus says copper is poisonous in large amounts. [2] Wilson disease is a rare inherited disorder that prevents the body from getting rid of extra copper; it can damage the brain, kidneys and eyes, and MedlinePlus says people with it should not take multivitamins that contain copper. [6] Treatment is specialist-led and lifelong. If you have Wilson disease or liver disease, ask your specialist before any copper or multi-mineral product; see Liver safety.Evidence by use
Copper supplements are sometimes marketed for joints, hair or skin. Proper evidence not found for benefit in people with adequate copper in the sources we read (NHS, MedlinePlus, the 2018 deficiency review). The established use is correcting a documented deficiency. [4]Frequently asked questions
Do I need a copper supplement if I take zinc?
Not automatically. The NHS says high zinc lowers copper absorption, so keeping zinc within limits and asking a clinician about testing comes first. [1]
What happens if I get too much copper?
The NHS lists stomach pain, sickness, diarrhea and, with long-term excess, liver and kidney damage. [1]
What foods are rich in copper?
Shellfish, nuts, organ meats, whole grains, beans and cocoa are named by the NHS and MedlinePlus. [1][2]
What is Wilson disease?
A rare inherited condition where copper builds up in the liver, brain and other organs. It needs specialist care. [6]
Is copper in tap water or cookware a concern?
The NHS 10 mg limit includes copper from food, water and supplements. We found no source on cookware, so: Proper evidence not found. [1]
More details: evidence, limits and cautions
The details behind this page: cautions, limits of the evidence and where sources disagree. Open any note to read it.
Medicines, pregnancy and children
References
- NHS, Vitamins and minerals: Others (chromium, copper, manganese, molybdenum, selenium, salt, zinc; page last reviewed 3 August 2020). Read 2026-10-22.
- MedlinePlus Medical Encyclopedia, Copper in diet. Read 2026-10-22.
- EFSA, Overview on Tolerable Upper Intake Levels as derived by the SCF and the EFSA NDA Panel, version 11 (August 2025). Read 2026-10-22.
- Copper deficiency anemia: review article. 2018. PubMed 29959467. Read 2026-10-22.
- Zinc-induced hematologic toxicities: a systematic review of descriptive studies. Biol Trace Elem Res. 2026. PubMed 42087025. Read 2026-10-22.
- MedlinePlus, Wilson Disease. Read 2026-10-22.