Researchers reviewed medical cases showing that not getting enough copper in your diet can seriously hurt your eyesight. In one dramatic example, a middle-aged woman who could barely see improved dramatically after taking copper supplements for 10 months. While copper deficiency causing vision problems is rare, doctors should know about it because it’s treatable. The study looked at about a dozen medical cases and discussed how to test for copper deficiency and the best ways to treat it with supplements.

The Quick Take

  • What they studied: Whether not having enough copper in your body can cause vision problems and how to fix it
  • Who participated: A review of about a dozen medical cases from published studies, including one detailed example of a middle-aged woman with severe vision loss
  • Key finding: One woman’s vision improved from being almost completely blind (20/400) to nearly perfect (20/25) after taking copper supplements for 10 months, suggesting copper deficiency can cause reversible vision loss
  • What it means for you: If you’re experiencing unexplained vision problems, your doctor should consider checking your copper levels, especially if other causes have been ruled out. However, copper deficiency is uncommon, so this wouldn’t be the first thing to check.

The Research Details

This was a review article, meaning researchers collected and summarized information from about a dozen existing medical studies and case reports about copper deficiency and vision problems. Rather than conducting their own experiment, they looked at what other doctors had already published about patients who had this condition. They organized the information to help other doctors understand how copper deficiency affects the eyes, how to test for it, and how to treat it. The researchers also discussed different types of copper supplements and how much copper people typically need to take to recover.

Review articles like this are important because they pull together scattered information from many different cases and studies into one place. This helps doctors recognize patterns they might miss if they only saw one or two cases. By collecting these cases, the researchers showed that copper deficiency is a real cause of vision loss that doctors should think about, even though it’s uncommon.

This is a review article rather than a controlled study, which means it’s based on collecting existing information rather than testing something new. The strength of this work depends on the quality of the original studies reviewed. The authors acknowledge that information about the best dose, form, and length of copper treatment is not well-defined, meaning more research is needed to give clearer guidelines.

What the Results Show

The most striking finding was a case of a middle-aged woman whose vision was severely impaired (measured as 20/400, meaning she could only see at 20 feet what a person with normal vision could see at 400 feet). After taking copper supplements for 10 months, her vision improved dramatically to 20/25, which is nearly perfect. This case demonstrates that vision loss from copper deficiency can be reversed if caught and treated. The review of about a dozen medical articles confirmed that copper deficiency can indeed cause vision problems in multiple patients, not just one isolated case.

The researchers found that a blood test measuring an enzyme called superoxide dismutase in red blood cells is one of the most reliable ways to detect copper deficiency. They also noted that copper gluconate appears to be the preferred form of copper supplement. Most patients in the reviewed cases needed several milligrams of elemental copper daily for several months to recover, though the exact best dose and duration weren’t clearly established across all cases.

This review brings together scattered case reports that had been published separately, showing that copper deficiency causing vision loss is a recognized but uncommon condition. The research suggests this is an important condition for doctors to know about because it’s treatable, unlike many causes of vision loss. However, the authors note that more systematic research is needed to establish clear treatment guidelines.

This is a review of existing cases rather than a new controlled study, so the findings are limited by the quality and completeness of the original reports. The optimal dose, chemical form, duration, and route of copper treatment are not clearly defined, meaning doctors don’t have precise guidelines yet. The sample size is small (about a dozen cases), so we can’t know how common this problem really is. The review doesn’t include information about how to prevent copper deficiency or who is most at risk.

The Bottom Line

If you have unexplained vision loss and other causes have been ruled out, ask your doctor to check your copper levels. If deficiency is found, copper gluconate supplements appear to be the preferred treatment, typically requiring several months of daily supplementation. However, this should only be done under medical supervision, as too much copper can also be harmful.

People experiencing unexplained vision problems should be aware of this possibility, and doctors should consider copper deficiency as a potential cause. People at higher risk might include those with certain digestive disorders that affect nutrient absorption, people on long-term parenteral nutrition (IV feeding), or those taking excessive zinc supplements (which can interfere with copper absorption). Most people eating a balanced diet get enough copper naturally.

Based on the case presented, significant vision improvement may take several months of consistent copper supplementation—in the example given, it took 10 months to see dramatic improvement. Results may vary depending on the severity of the deficiency and how long it had been present.

Want to Apply This Research?

  • If you’ve been diagnosed with copper deficiency and are taking supplements, track your daily copper intake (in milligrams) and any changes in vision clarity using a simple 1-10 scale. Note any other symptoms like fatigue or numbness that might also improve.
  • Set a daily reminder to take your copper supplement at the same time each day, and log it in your app. Also track foods naturally rich in copper (shellfish, nuts, seeds, whole grains, chocolate) to ensure you’re getting dietary copper as well.
  • Schedule monthly check-ins with your doctor to monitor vision changes and copper levels. Use the app to track vision improvements, energy levels, and any side effects. Keep a log of your supplement adherence to share with your healthcare provider at follow-up appointments.

This article summarizes research about copper deficiency and vision loss. Copper deficiency is rare and vision loss has many causes. If you’re experiencing vision problems, consult an eye doctor or your primary care physician for proper diagnosis before considering copper supplementation. Do not self-diagnose or self-treat with copper supplements without medical supervision, as excessive copper intake can be toxic. This information is educational and should not replace professional medical advice, diagnosis, or treatment.