Trace minerals
Copper
Iron metabolism
Cytochrome c oxidase, ceruloplasmin, iron transport.
Upper-limit caution
The Tolerable Upper Intake Level for Copper is 10 mg per day. Routine intakes above this level — counting food + supplements — raise the risk of adverse effects. Multivitamins, fortified foods, and standalone supplements stack faster than people expect.
What Copper does
Copper is required for cytochrome c oxidase (the terminal step of the electron transport chain), Cu-Zn superoxide dismutase, ceruloplasmin (iron transport), lysyl oxidase (collagen and elastin cross-linking), and dopamine beta-hydroxylase. The most common cause of copper deficiency in modern populations is over-supplementation with zinc — which is why a copper-to-zinc ratio matters in any high-zinc protocol. Wilson's disease (genetic copper accumulation) is the rare flip side and requires copper restriction.
Food sources of Copper
Approximate Copper content per serving. Whole-food intake counts toward your daily total alongside any supplemental dose.
| Food | Serving | Copper |
|---|---|---|
| Beef liver (cooked) | 3 oz | 12 mg |
| Oysters (cooked) | 3 oz | 4 mg |
| Cashews | 1 oz | 0.6 mg |
| Sunflower seeds | 1 oz | 0.5 mg |
| Dark chocolate (70%+) | 1 oz | 0.5 mg |
| Cooked shiitake mushrooms | 1/2 cup | 0.65 mg |
Signs of Copper deficiency
- ●Anemia that looks like iron deficiency but doesn't respond to iron
- ●Neutropenia (low white blood cell count)
- ●Myelopathy: gait instability, paresthesias, sensory ataxia (looks like B12 deficiency)
- ●Hypopigmentation of hair and skin
- ●Connective tissue weakness, vascular fragility
Who needs more Copper
Groups and situations where Copper requirements rise or status commonly runs low:
- ●Anyone supplementing high-dose zinc (>40 mg/day) without paired copper
- ●Bariatric surgery patients, especially gastric bypass
- ●Long-term denture-cream users (older formulas contained zinc that displaced copper)
- ●Severe malabsorption, celiac, IBD
How Copper appears on labels
Supplement labels list Copper under several names depending on the chemical form used. Any of these on an ingredients panel counts toward your Copper intake:
- copper
- copper bisglycinate
- copper sulfate
- copper gluconate
Best supplements for Copper
Top-scoring supplements in our catalog that list Copper on the label. Each product is graded on Formulate's ingredient-level rubric — dose accuracy, form, transparency, and third-party testing.
Deep dive
For mechanism of action, dosing protocols, evidence grade, and interaction warnings on Copper, see the full encyclopedia entry:
Copper encyclopedia entry →Research on Copper
Peer-reviewed studies in our research database that reference Copper. Each entry links to a detailed methodology review.
Guides covering Copper
Long-form articles in our guide library that go deeper on Copper — comparisons, protocols, and reviews.
Frequently asked questions
What is the daily target for Copper?
What foods are highest in Copper?
What is the best form of Copper to supplement?
What are the signs of Copper deficiency?
Who is most at risk for low Copper?
Related trace minerals
Track your full intake
Formulate's free web app aggregates Copper (and ~40 other nutrients) across every supplement in your stack — flagging underdoses, overlaps, and upper-limit overshoots in one view.
Track your intake free →Medical disclaimer. This page is educational and does not replace advice from a qualified healthcare provider. Targets and upper limits are general adult reference values; individual needs vary by age, sex, pregnancy status, and clinical context.