Copper deficiency, toxicity and supplementation in children 

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What Is Copper and Why Is It Important?

Copper is a trace mineral found in all tissues and fluids of the body. Though required only in small amounts, it plays a crucial role in multiple biological systems. Copper acts as a cofactor for numerous enzymes involved in cellular energy production, iron metabolism, neurotransmitter synthesis, and antioxidant defense. One of its most important roles is in the enzyme superoxide dismutase (SOD), which protects cells from oxidative damage. Copper also supports connective tissue synthesis (collagen and elastin), immune function, blood clotting, hormone activation, gene expression, and the formation of new blood vessels.

In early brain development, copper is vital for proper myelination and neurotransmission. Abnormal copper levels—either too high or too low—can result in a wide range of systemic and neurological symptoms.

Food Sources of Copper

Copper is found in both plant and animal foods. Rich sources include:

• Organ meats (especially liver)
• Shellfish (especially oysters and crab)
• Cashews, sunflower seeds, sesame seeds
• Legumes
• Potatoes
• Whole grains
• Cocoa and dark chocolate
• Tofu
• Dried fruits (like figs)

Recommended Dietary Allowance (RDA)

Copper needs vary by age:

• 0–6 months: 200 mcg/day
• 7–12 months: 220 mcg/day
• 1–3 years: 340 mcg/day
• 4–8 years: 440 mcg/day
• 9–13 years: 700 mcg/day
• 14–18 years: 890 mcg/day
• Adults: 900 mcg/day

Pregnancy and lactation increase needs slightly. Copper deficiency is rare in healthy children who consume a varied diet.

Signs of Copper Deficiency

Though uncommon, copper deficiency can have wide-reaching effects. It most often presents with:

• Hypochromic, microcytic anemia that doesn’t respond to iron
• Depigmentation of skin or hair
• Neurological issues (numbness, tingling, limb weakness)
• Fatigue or lethargy
• Recurrent infections or weakened immunity

Functional copper deficiency may occur in those with malabsorption (celiac disease, IBD), chronic diarrhea, or those taking proton pump inhibitors. It is also frequently seen in individuals who take high-dose zinc supplements long-term. Zinc and copper compete for absorption through the same transporter; excess zinc (>50 mg/day for more than 6 months) can deplete copper stores.

Clinical Pearl:

If a patient presents with unexplained anemia that is unresponsive to iron, or neurologic symptoms without B12 deficiency, consider checking serum copper and ceruloplasmin.

Signs of Copper Toxicity

Copper toxicity is rare but may occur from environmental exposure (e.g., contaminated water), excessive supplementation, or the genetic disorder Wilson’s disease. Symptoms include:

• Nausea, vomiting, abdominal pain
• Diarrhea
• Jaundice
• Blood in urine or decreased urination
• Neurological symptoms (tremors, confusion)

In Wilson’s disease, copper accumulates due to defective biliary excretion, leading to liver, brain, and kidney damage. A hallmark sign is the presence of Kayser-Fleischer rings in the eyes. Treatment involves chelating agents like penicillamine.

Testing Copper Levels

Copper status is typically evaluated using:

• Serum copper: Measures circulating copper but may be affected by acute illness or diet.
• Ceruloplasmin: The primary copper-carrying protein; low levels may reflect deficiency or Wilson’s disease.
• Additional tests (urine copper, liver biopsy, genetic testing) may be needed in complex cases.

The ideal zinc:copper ratio in serum is roughly 0.7 to 1.0. High zinc with low copper often suggests a functional deficiency.

Clinical Uses of Copper in Naturopathic Medicine

Autism Spectrum Disorder (ASD)

Children with ASD often present with altered mineral metabolism. Research shows they are more likely to have low zinc, high copper, and a disrupted zinc:copper ratio. Elevated copper may contribute to oxidative stress and neurotransmitter imbalance (especially dopamine and norepinephrine). Some studies have shown behavioral improvement in children with ASD and GI disease after zinc therapy, which may help correct the zinc:copper ratio. However, more research is needed, and not all children with ASD have copper dysregulation.

ADHD

Research on copper and ADHD is limited, but several studies suggest that an elevated copper:zinc ratio may correlate with ADHD symptoms. It is unclear whether copper excess or deficiency plays a stronger role, but some researchers suggest that altered copper metabolism may contribute to hyperactivity or cognitive dysfunction. More clinical trials are needed.

Celiac Disease

Copper deficiency has been documented in children and adults with untreated or poorly managed celiac disease. Malabsorption impairs copper uptake and may contribute to anemia, neurologic symptoms, or connective tissue dysfunction. In most cases, a high-quality gluten-free diet along with copper repletion resolves symptoms.

Supplementation and Safety

Copper is usually supplemented as part of a multimineral formula, often in the form of copper gluconate, sulfate, or bisglycinate. Copper supplementation is generally unnecessary unless there is:

• Documented deficiency
• Long-term high-dose zinc use
• Malabsorptive condition (e.g., IBD or celiac disease)

Copper supplementation is not recommended without lab testing. Over-supplementation can be dangerous. If zinc is being supplemented at 50 mg or more daily for over 3 months, 1–2 mg of copper should be added to maintain balance.

Whole food sources of copper are safe and preferable for most individuals.

Summary

Copper is a critical trace mineral involved in numerous processes including iron metabolism, energy production, antioxidant defense, and brain function. While deficiency is rare, it can lead to anemia, immune dysfunction, and neurological symptoms. Excess copper is also harmful and most often due to environmental exposure or genetic disorders.

Conditions that may warrant closer copper monitoring include:

• Autism spectrum disorder
• ADHD
• Celiac disease
• Chronic high-dose zinc supplementation

Copper supplementation should always be guided by lab testing and medical supervision.

Disclaimer: This article is for educational purposes only and does not substitute for medical advice. Always consult your healthcare provider before beginning any new supplements.

Resources: 

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This article was researched by Kayla Martin, CNS and edited by Erika Krumbeck, ND.