Minerals
Copper
Copper is an essential trace mineral that your body needs in small amounts. It is involved in energy production, iron metabolism and connective-tissue formation.
You obtain copper through your diet. In the body, it acts as a component of enzymes that enable important metabolic processes. Chemically, copper is an element with the symbol Cu—not a food or a particular copper compound. Small amounts are essential, but excessive intake can be harmful.
Copper is an essential trace mineral that your body needs in small amounts. As part of various enzymes, it is involved in important metabolic processes. Chemically, copper is an element with the symbol Cu—not a food or a single copper compound.
What does your body use copper for?
Copper contributes to the maintenance of normal connective tissue, normal energy-yielding metabolism, and the normal function of the nervous and immune systems. It also contributes to normal iron transport, normal hair and skin pigmentation, and the protection of cells from oxidative stress. These claims describe normal body functions; they do not mean that copper supplements provide an extra benefit when your intake is already adequate.
How much copper do you need?
EFSA’s adequate daily intake is 1.6 mg for adult men, 1.3 mg for adult women, and 1.5 mg during pregnancy and breastfeeding. These are reference values for total intake from all sources, not recommended supplement doses. The EU nutrient reference value used for food labelling is 1 mg per day.
In 2023, EFSA set an acceptable daily intake of 0.07 mg of copper per kg of body weight. For adults, this is about 5 mg per day. This safety value is not a target intake. Older European upper intake levels for children range from 1 to 4 mg per day, depending on age.
Copper and health: what does the evidence show?
Evidence for some potential additional effects is limited. A small meta-analysis found no statistically demonstrable effect of copper supplements on total, LDL or HDL cholesterol. Observational studies linked higher dietary copper intake with slightly higher bone density in the lumbar spine; this does not establish a benefit from supplements. There is also insufficient evidence that copper supplements improve blood-glucose regulation or cognitive function.
A meta-analysis of cohort studies found an association between higher copper concentrations in blood and a higher risk of stroke and cardiovascular mortality. It measured copper in blood, not the effect of taking copper. It therefore cannot show that copper from food or supplements causes these risks.
When should you take care?
Long-term use of high-dose zinc supplements can inhibit copper absorption and contribute to copper deficiency. If you have Wilson disease, or take trientine, D-penicillamine or medical zinc to lower copper, do not add copper unless your specialist tells you to. Ask a clinician before using copper supplements if bile excretion is impaired. Give infants copper only for a medical reason and with professional supervision. During pregnancy and breastfeeding, discuss high-dose supplements with a health professional.
How nutrition works
Connective tissue
Energy metabolism
Nervous system
Skin, hair and nails
Copper contributes to normal hair pigmentation. [1]
Iron metabolism
Immune system
Protection from oxidative stress
Blood cholesterol
Copper supplementation showed no statistically significant effect on total, LDL or HDL cholesterol in a small meta-analysis of randomised trials. [3]
Bone health
Higher dietary copper intake was associated with slightly higher lumbar-spine bone mineral density in observational studies. [4]
Glycaemic control
There is insufficient evidence that copper supplementation alone improves blood glucose regulation. [5]
Cardiovascular health
Higher circulating copper concentrations were associated with a higher risk of stroke and cardiovascular mortality in cohort studies. [6]
Cognitive function
A small randomised trial in people with mild Alzheimer's disease found no statistically significant cognitive benefit from copper supplementation. [2]
Statements & evidence
Copper contributes to maintenance of normal connective tissues. [1][7]
This claim may be used only for foods that meet at least the conditions for being a source of copper. It describes normal physiology, not evidence that extra copper improves connective tissues when your intake is already adequate.
Copper contributes to normal energy-yielding metabolism. [1][7]
The food must qualify as at least a source of copper. This claim concerns normal energy metabolism, not a demonstrated increase in your energy or performance from additional copper.
Copper contributes to normal functioning of the nervous system. [1][7]
The claim is permitted for foods that qualify as at least a source of copper. It does not establish that copper supplements improve your memory or prevent neurological disease.
Copper contributes to normal hair pigmentation. [1][7]
The food must qualify as at least a source of copper. The authorised claim concerns normal pigment formation; it does not show that additional copper reverses grey hair.
Copper contributes to normal iron transport in the body. [1][7]
The food must qualify as at least a source of copper. This describes copper’s role in normal iron transport, not a general recommendation to take copper for iron deficiency.
Copper contributes to normal skin pigmentation. [1][7]
The claim is permitted for foods that qualify as at least a source of copper. It concerns normal pigment formation, not evidence that copper supplements tan your skin or protect it from UV radiation.
Copper contributes to the normal function of the immune system. [1][7]
The food must qualify as at least a source of copper. Supporting normal immune function is not the same as boosting your immunity or demonstrating protection against infections through supplementation.
Copper contributes to the protection of cells from oxidative stress. [1][7]
The food must qualify as at least a source of copper. The claim describes a normal protective function; it does not establish that higher copper intakes slow ageing or prevent disease.
Copper supplementation showed no statistically significant effect on total, LDL or HDL cholesterol in a small meta-analysis of randomised trials. [3]
The meta-analysis included five trials with 176 participants. The small evidence base and imprecise estimates limit confidence: a non-significant result does not prove that there is no effect. The available abstract does not establish the complete supplementation dose range.
Higher dietary copper intake was associated with slightly higher lumbar-spine bone mineral density in observational studies. [4]
A 2025 meta-analysis found this association in three studies with 9,059 participants; hip findings were not statistically significant. Other dietary and lifestyle factors may explain the association. These data do not demonstrate that copper supplements improve bone density or prevent fractures.
There is insufficient evidence that copper supplementation alone improves blood glucose regulation. [5]
A 2023 systematic review covered adults with and without type 2 diabetes. Most studies were observational, with only two randomised trials. At least one intervention used a combined vitamin and mineral preparation, so any effects could not be attributed specifically to copper.
Higher circulating copper concentrations were associated with a higher risk of stroke and cardiovascular mortality in cohort studies. [6]
A 2024 meta-analysis included 17 cohort studies with 47,813 participants. The authors rated most associations as moderate certainty using GRADE. The exposure was circulating copper, not an administered copper dose. The results do not establish that dietary copper causes these events or that reducing intake prevents them.
A small randomised trial in people with mild Alzheimer’s disease found no statistically significant cognitive benefit from copper supplementation. [2]
The trial summarised by NIH ODS included 68 people aged 50–80 and lasted 12 months. It does not provide sufficient evidence for cognitive improvement or Alzheimer’s prevention through copper supplementation. Observed differences in blood copper are also not evidence of supplementation benefit.
EFSA’s adequate daily intakes for copper are 1.6 mg for adult men, 1.3 mg for adult women, and 1.5 mg during pregnancy and lactation. [8]
These reference values concern your total intake, not supplements alone. They are not doses established to produce additional health benefits. EFSA could not set an average requirement or population reference intake because biomarker and balance-study evidence was inadequate.
In 2023, EFSA established an acceptable daily copper intake of 0.07 mg per kg body weight for adults; this safety value is not a recommended supplement dose. [9]
The value concerns total exposure. EFSA noted that copper retention was not expected at an intake of 5 mg per day. Excessive accumulation can damage the liver, so more copper is not necessarily better for you.
Safety information
Caution
Large ingestions can cause severe poisoning
Swallowing large amounts, particularly soluble copper salts, can cause severe gastrointestinal injury, breakdown of red blood cells, kidney and liver injury, and potentially death. Suspected poisoning requires immediate medical advice; this does not describe ordinary dietary copper intake. [14]
Upper level · Adults
European safety values apply to total intake
In 2023, EFSA established an acceptable daily intake (ADI) of 0.07 mg copper per kg body weight, described as approximately 5 mg daily for adults. The older European adult tolerable upper intake level (UL) is also 5 mg daily. ADI and UL are distinct assessment measures: neither is a target intake or a recommended supplement dose. Consider food, drinking water and supplements together. [13][15]
Upper level · Children and adolescents (1–17 years)
Children have lower upper intake levels
The older European ULs for total daily intake are: ages 1–3 years, 1 mg; 4–6 years, 2 mg; 7–10 years, 3 mg; 11–14 years, 4 mg; and 15–17 years, 4 mg. These are not recommended supplement doses or newly derived paediatric limits from EFSA's 2023 assessment. [15]
Caution
BfR recommends a low copper amount in supplements
BfR proposes a maximum of 1 mg copper per recommended daily portion of an adult supplement, with advice that it is unsuitable for children and adolescents. This is a product-composition recommendation, not a legal limit or a UL for total intake. [16]
Interaction
High zinc intake can cause copper deficiency
Prolonged excessive zinc intake can inhibit intestinal copper absorption and cause copper deficiency. This includes high-dose zinc supplements and excessive use of zinc-containing denture adhesives. Seek professional assessment rather than adding high-dose copper yourself. [2]
Contraindication
Do not supplement copper without specialist advice in Wilson's disease
If you have Wilson's disease, take copper supplements only under explicit specialist direction. Impaired copper clearance increases the risk of harmful accumulation; general-population safety values cannot be assumed protective. Dietary changes should follow your individual treatment plan. [2]
Interaction
Coordinate copper supplements with copper-lowering treatment
If you receive trientine, D-penicillamine or medicinal zinc to lower copper, do not add copper independently. Additional copper may work against the treatment objective. Follow medicine-specific spacing instructions; there is no established universal spacing rule for copper and all medicines. [17][18][2]
Caution
Review copper supplements if biliary excretion is impaired
If you have cholestasis, biliary dysfunction or cirrhosis, seek medical advice before taking copper supplements because excretion through bile may be impaired. Explicit warnings come from injectable-copper labelling; they do not establish a blanket prohibition on copper-containing foods in every liver disorder. [19]
Caution
Do not independently give copper supplements to infants
No UL has been established for infants; this does not mean unrestricted additional intake is safe. Breast milk, infant formula and age-appropriate food are the intended copper sources. Additional supplementation should be medically indicated and professionally supervised. [2]
Caution
Review high-dose copper during pregnancy and breastfeeding
If you are pregnant or breastfeeding, do not take high-dose copper supplements without professional advice. The EFSA summary does not establish separate ULs for these groups; this is not evidence that additional high doses are safe. Include copper from other supplements when assessing intake. [15][2]
Found in
Frequently asked questions
How much copper do I need each day?
According to EFSA, the adequate daily intake is 1.6 mg for adult men and 1.3 mg for adult women. It is 1.5 mg during pregnancy and breastfeeding.
What does the body need copper for?
Copper contributes to normal connective tissue, energy metabolism, nervous system function and iron transport. It also contributes to normal immune function and the protection of cells from oxidative stress.
Should I take copper supplements?
The draft does not establish benefits of copper supplements for blood-glucose regulation or cognition; a small meta-analysis also found no statistically detectable effect on blood lipids. If you have Wilson’s disease, do not take copper without specialist advice.
Can too much copper be harmful?
Yes. Too much copper can cause gastrointestinal symptoms, and sustained high intake can damage the liver. In 2023, EFSA set an acceptable daily total intake for adults of 0.07 mg per kg of body weight; this is not a recommended supplement dose.
More entries
Calcium
Calcium is an essential mineral. It provides structure to bones and teeth and contributes to normal muscle function, nerve transmission and blood clotting.
Iodine
Iodine is an essential trace mineral. Your body needs it to make thyroid hormones, which help regulate metabolism and support growth and development.
Iron
Iron is an essential trace element and a component of haemoglobin, which transports oxygen in the blood.
Phosphorus
Phosphorus is an essential mineral classified as a major mineral. It forms part of bones, teeth and cell structures and is involved in energy transfer within cells.
Selenium
Selenium is an essential trace element. Your body needs small amounts to make selenium-containing proteins involved in thyroid hormone metabolism and protection against oxidative damage.
Zinc
Zinc is an essential trace element that you obtain through your diet. It has important roles in enzymes and other proteins.
Sources
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- 02National Institutes of Health, Office of Dietary SupplementsCopper - Health Professional Fact SheetOpen source
- 032021Effects of Copper Supplementation on Blood Lipid Level: a Systematic Review and a Meta-Analysis on Randomized Clinical TrialsPubMed 33030656Open source
- 042025Dietary Copper Intake and Bone Health: A Systematic Review and Meta-Analysis of Observational StudiesOpen source
- 052023The Role of Copper Intake in the Development and Management of Type 2 Diabetes: A Systematic ReviewOpen source
- 062024Circulating copper levels and the risk of cardio-cerebrovascular diseases and cardiovascular and all-cause mortality: A systematic review and meta-analysis of longitudinal studiesPubMed 37852312Open source
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