About
What it is and where it shows up.
Copper is an essential trace mineral that functions as a cofactor for numerous metalloenzymes, supporting energy metabolism, connective tissue formation, iron absorption, and antioxidant defence. It is used as a nutritional supplement and fortifier in foods, infant formula, and animal feed.
Safety summary
The regulatory and scientific consensus.
Both deficiency and excess copper are harmful; EFSA (2023) revised the Acceptable Daily Intake downward to 0.07 mg/kg body weight per day (≈4.9 mg/day for a 70 kg adult), citing hepatic copper retention as an early marker of toxicity. The US IOM Tolerable Upper Intake Level for adults is 10 mg/day, based on prevention of liver damage. Individuals with Wilson's disease face critical risk of copper accumulation due to a genetic defect in biliary copper excretion.
Regulatory landscape
What food-safety regulators have decided.
| Jurisdiction | Status | Note |
|---|---|---|
| FSANZ (Food Standards Australia New Zealand) (Australia) | Approved | Copper is listed as a permitted nutritional supplement in the Australia New Zealand Food Standards Code; specific per-food limits are set within relevant standards for fortified foods. Precise confirmed upper intake value not retrieved from available sources.source |
| EFSA (European Food Safety Authority) (European Union) | Approved | EFSA Scientific Committee (2023) established ADI of 0.07 mg/kg bw/day, replacing prior UL of 5 mg/day for adults (SCF 2003). The 4.9 mg/day figure represents the ADI for a reference 70 kg adult. ADI applies across food additives, pesticides, and feed additives. Minimum and maximum copper limits for infant formula and follow-on formula are set separately under EC Regulation 609/2013.source |
| FSSAI (Food Safety and Standards Authority of India) (India) | Approved | Copper is regulated as a metal contaminant with food-category-specific limits under the Food Safety and Standards (Contaminants, Toxins and Residues) Regulations, 2011. It is also permitted as a nutritional supplement ingredient under the Health Supplement and Nutraceuticals regulations. No standalone FSSAI ADI or UL for copper as a nutrient could be confirmed from available public documents.source |
| FDA (Food and Drug Administration) (United States) | Approved | Copper gluconate (21 CFR 182.5260, 182.1260) and copper sulfate (21 CFR 184.1261) are GRAS as nutritional dietary supplements at GMP levels in any food. Cuprous iodide is GRAS at <0.01% in table salt as a source of dietary iodine (21 CFR 184.1265). IOM Tolerable Upper Intake Level (UL) for adults is 10 mg/day; FDA Daily Value is 0.9 mg/day for adults and children ≥4 years. |
Who should approach with care
Whose guidance would steer them away.
Liver Disease — Wilson's disease patients have a genetic defect (ATP7B mutation) that impairs biliary copper clearance, leading to abnormally high hepatic copper accumulation, cirrhosis, neurological damage, and risk of acute liver failure even at normal dietary intake.
Infants — Infant formula and follow-on formula are major contributors to copper exposure in infants; regulatory limits are tightly set under EC Regulation 609/2013 (EU) and equivalent standards, and supplemental copper beyond formula is generally unnecessary.
Kidney Disease — Impaired renal function can reduce urinary copper excretion and increase risk of systemic accumulation; supplemental copper use should be medically supervised in patients with significant kidney disease.
Children — EFSA (2023) notes that while higher growth-related nutrient requirements make adverse effects at the ADI less probable in children, exposure should still be monitored and supplementation kept within age-specific upper intake levels.
— Individuals taking high-dose copper supplements (approaching or exceeding the 10 mg/day UL) should consult a doctor, as chronic excess has been associated with liver enzyme elevation and, at extreme doses (30–60 mg/day), acute liver failure even without a known genetic disorder.
Research citations
The sources behind this verdict.
- 1other. Copper – Health Professional Fact Sheet (NIH Office of Dietary Supplements). ods.od.nih.gov
- 2FDA. FDA Food Additive Status List – Copper entries (21 CFR 182.5260, 182.1260, 184.1261, 184.1265), 2026. fda.gov
- 3PubMed. Is Copper Still Safe for Us? What Do We Know and What Are the Latest Literature Statements?, 2024. pmc.ncbi.nlm.nih.gov
- 4EFSA. Scientific Opinion on the re-evaluation of the existing health-based guidance values for copper and exposure assessment from all sources, 2023. efsa.europa.eu
- 5other. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc – Copper chapter (IOM/National Academies), 2001. ncbi.nlm.nih.gov
Independently researched5 citations