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In 2015, the fourth Korea National Health and Nutrition Examination Survey (KNHANES IV), conducted a study linking mercury exposure with glaucoma. The study used information from 2,680 participants to look for a correlation between glaucoma and trace metals in the body, specifically manganese, mercury, lead, cadmium, and arsenic.
The researchers found that lower blood levels of manganese, and higher blood levels of mercury, were associated with an increased chance of getting glaucoma. While these results are far from comprehensive or confirmed, the association between trace metals and glaucoma could offer a whole new approach to glaucoma treatment and possibly prevention.
Mercury is a naturally-occurring element that is found almost everywhere. In one form or another, it is in the air, the water, and the ground. One very toxic form of it—methylmercury—is well known to build up in fish, shellfish, and those that eat fish, including humans. Other major sources include fever thermometers, fluorescent lights, and silver fillings. While methylmercury is useful in many industrial and technological applications, if you get too much of it in your system it can harm the brain, nervous system, heart, kidneys, lungs, and immune system.1
Meanwhile, manganese is an essential trace metal that maintains proper cell function. It is also necessary for many enzymes, including superoxide dismutase, which inhibits the death of nerve cells.2
The researchers examined data from the study, which included demographic and health-related variables collected through personal interview, a self-administered questionnaire, physical and ophthalmologic examinations, and blood and urine sampling. After an ophthalmology-focused interview, participants underwent a thorough eye examination that included a variety of tests, examinations and imaging.
After adjusting for age, sex, exercise, and other factors, the researchers found that blood manganese levels were significantly lower in participants with glaucoma vs those without glaucoma. On the other hand, there were positive associations between higher blood mercury levels in those with glaucoma as opposed to those without the disease. The researchers found no such associations between glaucoma and blood lead, blood cadmium, or urine arsenic levels.3
It is important to keep in mind that this association between trace metals and glaucoma needs to be confirmed, and that more study is needed to better understand this purported connection. However, pursuing a healthy lifestyle and making sure you are getting enough manganese in your diet while cutting back on mercury can only help. There is no way to tell whether or not this will help prevent glaucoma without a lot more research, but it can’t hurt to try.
Make sure you are ingesting adequate manganese through food like nuts, seafood, seeds, whole wheat bread, tofu, beans and more, or supplements.4 As for mercury, you can keep this to a minimum by avoiding foods high in mercury such as seafood and fish, especially predatory fish such as tuna, swordfish, and shark, as well as any fish caught in waters contaminated with mercury, avoiding silver fillings, which can contain high levels of mercury, and avoiding environmental hazards that could expose you to mercury vapors, such as a broken florescent light.5
There will have to be additional research to confirm the Korean study’s initial findings that connected glaucoma with these trace metals. If their results are confirmed, it could open doors to treatments that make a real difference in the lives of glaucoma patients.
By contributing to Glaucoma Research Foundation, you are helping to move this kind of innovative research closer to better treatment options for patients. Be part of the cure, donate today.
1 Cunha, John P., DO. "Mercury Poisoning: Symptoms, Sources, Forms & Side Effects." Mercury Poisoning. MedicineNet, 12 Sept. 2016. Web. 14 Feb. 2017.
2 Finley JW, Davis CD. Manganese deficiency and toxicity: are high or low dietary amounts of manganese cause for concern? Biofactors. 1999;10(1):15-24.PubMedArticle
3 Lin S, Singh K, Lin SC. Association Between Body Levels of Trace Metals and Glaucoma Prevalence. JAMA Ophthalmol. 2015;133(10):1144-1150. doi:10.1001/jamaophthalmol.2015.2438
4 Whitbread, Daisy. "Top 10 Foods Highest in Manganese." Healthaliciousness.com. N.p., n.d. Web. 14 Feb. 2017.
5 Olson, David A., MD. "Mercury Toxicity Treatment & Management." Medscape. N.p., 13 Dec. 2016. Web. 15 Feb. 2017.
Last reviewed on March 03, 2017