Researchers have published the results of the first study to look at the relationship between caffeinated coffee and one type of glaucoma in U.S. residents. Their results suggest that consuming enough caffeinated coffee can cause vision loss or even blindness, a finding of major significance to those considered at-risk for glaucoma.
The scientists concluded that individuals who drink caffeinated coffee should limit how much they drink. Heavy consumption is linked to elevated risk of developing exfoliation glaucoma, ScienceDaily reports.
This type of glaucoma is the end result of pseudoexfoliation syndrome, which was identified by a Finnish ophthalmologist in 1917. The glaucoma that develops is the most common identifiable form of secondary open-angle glaucoma in the world, according to Medscape.
Scandinavian populations have the highest frequency of exfoliation syndrome in the world. The University of Iowa says patients with this condition develop deposits of white, flaky material like dandruff in many tissues of the eyes. As many as 50 percent of those who suffer from it develop exfoliation glaucoma.
The author of the study results, JaeHee Kang, ScD, of Brigham and Women's Hospital in Boston, says that Scandinavian populations also have the highest global consumption of caffeinated coffee. Researchers had already associated high caffeinated coffee intake with an elevated risk of primary open-angle glaucoma.
Study subjects included 78,977 women from the Nurses' Health Study and 41,202 men from the HealthProfessionals Follow-Up Study. All were at least 40 years old. None had glaucoma. All reported eye exams during a specified period.
The researchers collected information on the subjects' consumption of caffeinated beverages and reviewed their medical records to determine cases of exfoliation glaucoma. This disorder causes elevated eye pressure and damage to the optic nerve.
Compared to subjects who abstained, those who consumed at least three cups of caffeinated coffee a day showed an elevated risk of developing exfoliation glaucoma or at least some signs of it. However, the scientists acknowledge that more research is needed to better understand the causes of this type of glaucoma.
Twice a year for five years, pressure readings at an eye exam have caused my ophthalmologist to frown. They vary a little, around 20 or 21, in each eye. After checking my eyes thoroughly, she sighs and says that I don't quite have glaucoma -- yet. Fortunately, I don't drink coffee.
As someone who does admit to loving diet soda, which contains a significant amount of caffeine, I was initially alarmed when I read about this study. However, while the research team concluded that caffeinated coffee can cause vision loss, they found no link between drinking other caffeinated products like soda, tea, and chocolate and an elevated risk of developing this eye troublesome eye disease.
Vonda J. Sines has published thousands of print and online health and medical articles. She specializes in diseases and other conditions that affect the quality of life.