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The trace minerals copper and zinc must be in balance. Frequently, in children with ADHD, they are not.

A Potential Source of Toxic Copper Exposure: School Water Supplies

Many of our children are exposed to excess copper through a surprising source: school drinking water. While sampling data is sparse, as most schools are not required to monitor drinking water quality, a study from Massachusetts found that 9% of schools had one sample or more that exceeded allowable limits for copper (Ram 2019). Flushing the system periodically was found to have only modest impacts on reducing copper concentrations.

For the small percentage of schools and daycare centers that are required to monitor water contaminant levels, the data available also raises significant concerns. Copper levels exceeding the recommended limit were found in 13.2% of these facilities (Montagnino 2022).

Excess copper likely comes from copper water pipes and brass fittings. In cases where the water is more acidic or corrosive, copper levels are even higher due to the increased leaching of copper from the exposed metals. Exposure to excess copper could play a role in contributing to the symptoms of ADHD.

Copper and Zinc: A Delicate Balance

There are nine essential trace minerals. Several of them—including copper and zinc—are uniquely important in regulating brain function. And these two “mind minerals” can also play a key role in ADHD. What does that mean for the clinician who wants to take a comprehensive, whole-person approach to treating this disorder? In many cases, it can be crucial to determine a patient’s copper and zinc levels.

That’s because zinc and copper act like a nutritional see-saw: if levels of one go up, levels of the other go down. High zinc typically means low copper. High copper is usually associated with low zinc, although there can be exceptions.

And here’s the crucial fact about this ratio: in my own practice, I found that close to 50% of children with ADHD needed to correct imbalances in copper, zinc, or both. 

When I partnered with a parent and child to correct the problem, bringing the minerals back into balance, ADHD symptoms almost always improved—in some cases dramatically. Research even supports the importance of the copper/zinc ratio measured through blood levels (Skalny 2020), despite the fact that blood is known to be a poorer assessment of both copper and zinc status.

Too Much Copper Disrupts Neurotransmitter Function

Normal levels of copper are a must for good health, but too much can start to cause problems. Excess copper accumulates primarily in the liver and brain (Kardos 2018). And when present in excessive amounts, copper can cause damage through the process of oxidation, by tearing electrons from nearby atoms or molecules. This can lead to DNA damage, disrupted protein production and reduced cellular proliferation (Oe 2016).

In the brain, excess copper has been shown to cause swelling, degeneration, and decreased brain-cell survival, while also triggering the over-stimulation of neurons, a process referred to as “excitotoxicity.” For individuals with excess copper, the most common mental health conditions include personality disorders including antisocial behavior, irritability, and the inability to control inappropriate behavior (Tamacka 2021).

Zinc is Critical for Neurotransmitter Function

Zinc, as a mineral, is intimately involved with the synthesis and functioning of serotonin, norepinephrine, and dopamine (Doboszewska 2017). Balancing these neurotransmitters is at the core of effective treatment for the behaviors associated with ADHD.

And not only is zinc supportive of healthy brain function, zinc can also help to decrease excess copper. When copper levels are too high, zinc supplementation can help to bring back balance.

Scientific Support

Scientific research on ADHD also supports the zinc-copper connection. For example, studies show that:

  • ADHD children are often low in zinc. A meta-analysis from 2021 suggests that ADHD children may be prone to zinc deficiency and concluded that screening for zinc deficiency is a reasonable course of action (Ghoreishy 2021).
  • Zinc supplements improve ADHD symptoms. A separate meta-analysis of six studies on zinc supplementation for ADHD found that zinc had a significant effect on reducing total ADHD symptoms (Talebi 2022).
  • High copper and low zinc is a setup for ADHD symptoms. In a study of 108 children in Biological Trace Element Research, those with ADHD had lower zinc levels and a higher copper/zinc ratio as compared to healthy children without ADHD. And lower levels of zinc and higher copper/zinc ratios correlated with more severe inattentive ADHD symptoms (Viktorinova 2016).

Resources To Address Copper/Zinc Ratios—and ADHD

Our ADHD Intensive training is the most comprehensive Functional Medicine program available for ADHD. It is designed to help you more fully understand the underlying causes of ADHD, such as copper and zinc imbalances, and how to treat them effectively. This Intensive provides the tools you need to transform how you treat ADHD patients and greatly improve outcomes.

ADHD Intensive: March-May, 2024

Testing for and addressing an elevated copper/zinc ratio is another powerful tool in the clinical toolbox for reducing symptoms in patients with ADHD. I’d even say that understanding the copper/zinc ratio can be a game-changer in your treatment plan, And here’s another game-changer: our comprehensive ADHD intensive offered by Psychiatry Redefined.

This 10-week intensive training will give you the most comprehensive education for treating ADHD in children and adults, and helping them restore attention, minimize hyperactivity, and eliminate medication side effects. The training also includes eight group supervision discussions where you share real patient cases with me and our extraordinary faculty. You can think of this intensive as an instant community of supportive clinicians—clinicians who want to support your effectiveness as a practitioner and the well-being of your patients.

Are you ready to unlock the potential of the copper/zinc ratio in your ADHD treatment plan? Enroll now in the ADHD Intensive and gain the skills and support to truly make a difference with your patients. Click here to learn more and enroll!

Interested in this training, but have questions? Schedule a private call with Dr. Greenblatt for answers to your questions!

Ready to learn more evidence-based nutritional and functional approaches to help your patients?

Enroll now in our certified Fellowship for professionals! Book a private call with Dr. Greenblatt to learn more.

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Doboszewska U, Wlaź P, Nowak G, Radziwoń-Zaleska M, Cui R, Młyniec K. Zinc in the Monoaminergic Theory of Depression: Its Relationship to Neural Plasticity. Neural Plast. 2017;2017:3682752. doi:10.1155/2017/3682752

Ghoreishy SM, Ebrahimi Mousavi S, Asoudeh F, Mohammadi H. Zinc status in attention-deficit/hyperactivity disorder: a systematic review and meta-analysis of observational studies. Sci Rep. 2021;11(1):14612. Published 2021 Jul 16. doi:10.1038/s41598-021-94124-5

Kardos J, Héja L, Simon Á, Jablonkai I, Kovács R, Jemnitz K. Copper signalling: causes and consequences [published correction appears in Cell Commun Signal. 2018 Nov 12;16(1):80]. Cell Commun Signal. 2018;16(1):71. Published 2018 Oct 22. doi:10.1186/s12964-018-0277-3

Montagnino E, Lytle DA, Rose J, Cwiertny D, Whelton AJ. School and childcare center drinking water: Copper chemistry, health effects, occurrence, and remediation. AWWA Water Sci. 2022;4(2):e1270. doi:10.1002/aws2.1270

Oe S, Miyagawa K, Honma Y, Harada M. Copper induces hepatocyte injury due to the endoplasmic reticulum stress in cultured cells and patients with Wilson disease. Exp Cell Res. 2016;347(1):192-200. doi:10.1016/j.yexcr.2016.08.003

Ram KR. An Assessment of Lead and Copper in School Drinking Water. Dissertation. University of Massachusetts Amherst; 2019.

Skalny AV, Mazaletskaya AL, Ajsuvakova OP, et al. Serum zinc, copper, zinc-to-copper ratio, and other essential elements and minerals in children with attention deficit/hyperactivity disorder (ADHD). J Trace Elem Med Biol. 2020;58:126445. doi:10.1016/j.jtemb.2019.126445

Talebi S, Miraghajani M, Ghavami A, Mohammadi H. The effect of zinc supplementation in children with attention deficit hyperactivity disorder: A systematic review and dose-response meta‑analysis of randomized clinical trials. Crit Rev Food Sci Nutr. 2022;62(32):9093-9102. doi:10.1080/10408398.2021.1940833

Tarnacka B, Jopowicz A, Maślińska M. Copper, Iron, and Manganese Toxicity in Neuropsychiatric Conditions. Int J Mol Sci. 2021;22(15):7820. Published 2021 Jul 22. doi:10.3390/ijms22157820

Viktorinova A, Ursinyova M, Trebaticka J, Uhnakova I, Durackova Z, Masanova V. Changed Plasma Levels of Zinc and Copper to Zinc Ratio and Their Possible Associations with Parent- and Teacher-Rated Symptoms in Children with Attention-Deficit Hyperactivity Disorder. Biol Trace Elem Res. 2016;169(1):1-7. doi:10.1007/s12011-015-0395-3