Copper is an essential mineral involved in many functions we depend on daily—energy production, immune defense, iron metabolism, and connective tissue repair. But for those with a history of cancer, copper requires much closer attention. 

In my clinical practice, I often review supplement labels for my patients and find that most standard multivitamins include copper and zinc— usually in doses that raise concern. For the general population, this may not be an issue, but for cancer survivors, the relationship with copper is far more complex. Although it’s needed in trace amounts, research suggests that elevated copper levels may be linked to biological processes that support tumor growth and spread¹⁻². 

The Role of Copper in the Body 

Copper helps convert food into cellular energy. It also plays roles in maintaining nerve cells, supporting iron metabolism, regulating the immune system, and defending against oxidative stress³⁻⁴. But like all essential nutrients, it’s about balance. Too little can lead to deficiency symptoms; too much, however, can become a catalyst in processes we don’t want accelerated in the context of cancer—particularly angiogenesis. 

Angiogenesis: A Normal Process with Complex Cancer Implications 

Angiogenesis is the body’s natural process of forming new blood vessels. During normal healing, it helps repair wounds by delivering oxygen and nutrients to damaged tissue. Unfortunately, tumors can exploit this same mechanism to fuel their growth. Like all rapidly dividing cells, cancer cells require a steady supply of oxygen and nutrients—and angiogenesis helps them get it. The newly formed blood vessels supply the tumor as well⁵. 

Copper is one of several nutrients known to stimulate angiogenesis, fueling tumor development and metastatic potential⁵⁻⁶. Multiple studies have demonstrated this link, particularly in breast, prostate, and lung cancers¹⁻²,⁵. 

A study in Integrative Cancer Therapies explored how copper chelation (removing excess copper) may reduce angiogenesis and slow tumor progression². 

Research in Biological Trace Element Research and other journals found that patients with certain cancers—such as breast, prostate, and lung—often have elevated serum copper levels compared to the general population¹,⁵. 

In Bengtsson, T. et al, the authors found that patients with a higher serum copper-to-zinc ratio at diagnosis had significantly worse overall survival than those with a lower ratio¹. 

Why Most Multivitamins Get Copper (and Zinc) Wrong 

Many supplement companies include high doses of zinc in their multivitamins as a standard ingredient—usually without any medical need. This, in turn, over time, has been scientifically shown to reduce copper absorption³. Rather than lowering zinc to appropriate levels, manufacturers often add more copper to “balance” the formula—resulting in unnecessarily elevated serum copper levels³. 

It is undisputed that zinc is a valuable nutrient with well-documented roles in immune function and cellular repair (Read our blog on zinc here.) But it must be used at appropriate doses. When overdone, it drives copper and zinc out of balance, sometimes causing more harm than good³⁻⁴. 

Copper and Cancer: A Risk Survivors Shouldn’t Ignore 

It’s important for survivors to know that their body’s systems—especially those related to inflammation, cell turnover, and vascular growth—can remain sensitive long after active treatment ends. That includes how the body interacts with minerals like copper⁵⁻⁶. 

Although definitive clinical trials are still lacking, observational studies reveal a concerning pattern—enough that I routinely advise patients to avoid copper supplementation¹,². Most people obtain all the copper they need from a typical diet. Copper is found naturally in foods like nuts, seeds, whole grains, dark chocolate, and shellfish. Unless you were told by your doctor that you’re deficient, there’s usually no reason to supplement in the first place. 

For survivors, it’s not about fear—it’s about making informed, evidence-based decisions. Supplements should support your recovery, not quietly undermine it. That’s why oncologists, including myself, often recommend avoiding generic multivitamins—since nutritional needs after cancer are rarely one-size-fits-all⁶. 

So, What Can You Do? 

• Check your supplement labels and avoid copper.
• Be cautious with high-zinc supplements. Without proper balance, they can lead to copper overload.
• Avoid standard or generic multivitamins not specifically designed for survivors. 
• Don’t assume more is better, especially when it comes to minerals that interact with cancer biology. 

References 

• Bengtsson, T. et al. “Copper-to-zinc ratio as a long-term predictor of overall survival in breast cancer patients: A prospective cohort study.” Redox Biology, 2023. 
• Antoniades, V. et al. “The Role of Copper Chelation in Cancer Therapy.” Medical Hypotheses, 2013. 
• Brewer, G.J. “Copper Excess, Zinc Deficiency, and Metallothionein: Evidence for a Role in Cancer.” Integrative Cancer Therapies, 2010.
• Turski, M.L., Thiele, D.J. “New Roles for Copper Metabolism in Cell Proliferation, Signaling, and Disease.” Journal of Biological Chemistry, 2009.
• Nasulewicz, A., Mazur, A., Opolski, A. “Role of copper in tumour angiogenesis.” Polish Journal of Pathology, 2004. 
• Khan, G. & Merajver, S.D. “Copper chelation in cancer therapy using tetrathiomolybdate: an evolving paradigm.” Expert Opinion on Investigational Drugs, 2009.