Study reveals copper may raise fibromyalgia risk, iron could offer relief

By Dr. Chinta SidharthanReviewed by Susha Cheriyedath, M.Sc.Feb 3 2025

Could balancing trace elements like copper and iron be the key to managing fibromyalgia? A groundbreaking study uncovers a surprising link that could shape future treatments.

Study: Copper and iron as unique trace elements linked to fibromyalgia risk. Image Credit: Bignai / Shutterstock

Imagine living with constant pain, exhaustion, and cognitive fog. This is the reality for millions living with fibromyalgia. However, there is new hope, as a recent study published in the journal Scientific Reports reported a surprising link between trace elements and fibromyalgia risk, revealing that copper may increase susceptibility to fibromyalgia while iron could offer protection. Although the study suggests a potential causal link, further research is needed to confirm these findings.

Fibromyalgia

Fibromyalgia is a chronic condition that affects millions worldwide, causing widespread pain, fatigue, and cognitive difficulties. Despite extensive research, its exact causes remain elusive. Scientists believe that multiple factors, including genetic predisposition, neurotransmitter imbalances, and environmental influences, contribute to fibromyalgia.

Some studies suggest that trace elements, essential minerals involved in biological processes, may play a role in fibromyalgia development. Elements such as iron, zinc, magnesium, and copper are crucial for functions such as oxygen transport, nerve signaling, and immune regulation, and deficiencies or excesses in these elements have been linked to various health issues, including chronic pain conditions.

The Current Study

The present study used Mendelian randomization, a genetic epidemiology method that helps determine causal relationships between biological factors and diseases, to explore the link between fibromyalgia and trace elements. Researchers from the Guangzhou University of Chinese Medicine in China examined the connection between 15 trace elements and fibromyalgia risk by analyzing genome-wide association study (GWAS) data.

They extracted genetic instrumental variables, including specific genetic variations linked to trace element levels, from a large dataset of European individuals and employed a two-sample Mendelian randomization approach to assess whether trace elements directly impacted fibromyalgia.

Additionally, various statistical methods, such as inverse-variance weighting, weighted median, and weighted mode, were applied to ensure robust results. They also performed a multivariable Mendelian randomization analysis to rule out confounding variables, specifically controlling for selenium, which may influence iron and copper metabolism and thus affect fibromyalgia risk.

The study relied on genetic data from over 400,000 individuals, including nearly 2,700 fibromyalgia patients, sourced from the FinnGen project. However, to ensure the validity of their findings, the researchers selected only those single nucleotide polymorphisms (SNPs) that were strongly associated with trace element levels.

They also performed sensitivity tests, including heterogeneity analysis and numerous other assessments, to confirm the reliability of their results and detect any bias caused by pleiotropic effects, where genetic variants could be influencing fibromyalgia risk through pathways unrelated to trace elements.

Major Findings

The researchers reported that copper and iron have opposing effects on fibromyalgia risk. Elevated copper levels were associated with an increased risk of developing fibromyalgia, while higher iron levels appeared to reduce susceptibility.

The results from the Mendelian randomization analysis revealed a statistically significant positive correlation between copper levels and fibromyalgia risk. Specifically, individuals with genetically higher copper levels had a 9.5% increased likelihood of developing fibromyalgia.

While copper plays a crucial role in various bodily functions, including enzyme activity and connective tissue formation, excessive copper accumulation is known to lead to oxidative stress and inflammation. The researchers believe that these mechanisms may contribute to fibromyalgia symptoms such as heightened pain sensitivity and chronic fatigue.

On the other hand, the study identified iron as a potential protective factor against fibromyalgia. Individuals with genetically higher iron levels had a 56% lower risk of fibromyalgia. Iron is essential for oxygen transport, energy production, and neurotransmitter function, and iron deficiency has been linked to cognitive impairments, muscle pain, and fatigue — all of which are hallmark symptoms of fibromyalgia.

Previous studies have also reported that fibromyalgia patients tend to have lower iron levels, and iron supplementation has shown potential in alleviating some symptoms. Furthermore, even after adjusting for selenium, which can interact with both copper and iron metabolism, the associations remained significant, reinforcing the independent effects of these two elements on fibromyalgia risk.

The study ruled out pleiotropic effects and confirmed the robustness of the results through sensitivity analyses, further strengthening the evidence that these associations are unlikely to be due to confounding factors. However, the researchers caution that while the findings suggest a potential causal link, further studies in diverse populations are needed to confirm these relationships.

These findings highlighted the potential role of trace element balance in fibromyalgia. While further research is needed to validate a direct causal relationship, these results indicate that monitoring and adjusting copper and iron levels could be explored as a possible avenue for fibromyalgia prevention and management.

Conclusions

Overall, the study provided new evidence suggesting that copper and iron levels may influence fibromyalgia risk. Elevated levels of copper were linked to increased susceptibility, while iron levels were found to offer a protective effect.

These findings also underscore the importance of further investigation into dietary and therapeutic interventions for fibromyalgia aimed at optimizing trace element balance. Understanding these relationships could also lead to more effective fibromyalgia management strategies, offering hope to millions affected by this challenging condition.

However, the study primarily focused on individuals of European descent, meaning its findings may not be directly generalizable to other populations. Additionally, environmental and dietary factors that influence trace element levels were not fully explored, highlighting the need for further research in this area.