Our pick · Copper

Thorne Copper Bisglycinate 2mg

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Our pick

Thorne Copper Bisglycinate 2mg

NSF Certified for Sport, chelated bisglycinate for optimal absorption, third-party tested, 2mg dose

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Dosage

Typical Dose

1-2 mg/day is a common supplemental dose, often included in multivitamins. Standalone copper supplementation is typically 2 mg/day when offsetting zinc-induced depletion.

RDA

RDA: 900 mcg/day for adults.

Upper Limit

10,000 mcg (10 mg)/day for adults. Liver damage can occur with chronic excess.

Forms

Copper gluconate and copper bisglycinate are well-absorbed. Copper oxide is poorly absorbed. Copper sulfate is used in research but less common in supplements.

Safety

General

Safe at doses near the RDA. Copper has a wide safety margin between the RDA (0.9 mg) and UL (10 mg), but excess accumulation is a concern.

Cautions

Individuals with Wilson's disease must avoid copper supplements entirely.
Chronic excess may contribute to oxidative stress and has been loosely associated with Alzheimer's disease risk in some observational studies.
Most people get adequate copper from diet.

Interactions

High-dose zinc (50+ mg/day) depletes copper by competing for intestinal absorption — this is the most common reason for copper supplementation.
High-dose vitamin C may reduce copper absorption.
Iron and copper metabolism are interdependent.

Copper

An essential trace mineral required for energy production, connective tissue formation, and iron metabolism — rarely needed as a standalone supplement unless zinc supplementation depletes it.

Energy & Fatigue Joint & Bone

BEvidence

By editorialUpdated 2026-05-251 min read

What it's actually good for

Copper is an essential trace mineral that serves as a cofactor for enzymes involved in energy production (cytochrome c oxidase), iron metabolism (ceruloplasmin), connective tissue integrity (lysyl oxidase), and antioxidant defense (superoxide dismutase). Most people obtain adequate copper from shellfish, nuts, seeds, organ meats, and whole grains. The primary supplementation use case is preventing copper deficiency in people taking high-dose zinc (which blocks copper absorption over time). Standalone copper supplementation is rarely necessary and not advisable without a clear indication, given that excess copper can be pro-oxidant and is potentially harmful in accumulation disorders.

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Essential cofactor for enzymes involved in energy production and connective tissue

Copper is required for cytochrome c oxidase (mitochondrial energy), lysyl oxidase (collagen/elastin cross-linking), and ceruloplasmin (iron metabolism). Deficiency causes fatigue, anemia, and connective tissue abnormalities. Supplementation benefits are limited to those with deficiency or induced depletion.

Supports bone health through collagen cross-linking

Copper-dependent lysyl oxidase is essential for collagen and elastin cross-linking in bone matrix. Copper deficiency in animals causes osteoporosis-like bone changes. Human evidence for supplementation benefit is limited to deficiency correction.

Sources

1 cited

[01]GOVTCopper — Fact Sheet for Health ProfessionalsNIH Office of Dietary Supplements. 2024

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Medical disclaimer. The information on this site is provided for educational purposes only and is not intended as medical advice. It does not constitute a diagnosis, treatment plan, or recommendation for any specific health condition. Always consult a qualified healthcare professional before making changes to your supplement regimen, diet, or lifestyle — especially if you are pregnant, nursing, taking medications, or managing a medical condition.

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