If you drink hot tea, you might be getting an unexpected health benefit: A cup a day might reduce the risk of glaucoma.

Researchers from Brown University and the University of California made the discovery while studying whether drinking caffeinated and not-caffeinated beverages influences the risk of the sight-stealing eye disease.

Glaucoma damages the optic nerve when fluid builds up in the front part of the eye. About 2 percent of people over age 40 in North America have been diagnosed with glaucoma, according to the National Eye Institute.

The new study is the first time that a broad range of drinks — iced tea, hot tea, decaffeinated tea, coffee and soft drinks — have been examined for their potential influence on glaucoma. The findings were published in the British Journal of Ophthalmology.

The researchers analyzed medical information from about 10,000 people that was collected from a 2005 nationwide survey and included data from physical examinations, blood samples and glaucoma diagnoses. As part of the assessment, the participants also provided information about their beverage consumption habits.

Those who drank hot tea every day had a 74 percent lower risk of developing glaucoma than those who did not. More detailed information, such as how much tea was consumed each day and what kind of tea, was not available.

Still, the researchers noted that tea contains phytochemicals and flavonoids, which are known to have antioxidant and anti-inflammatory properties.

So, the next you steep your favorite cup of tea, know that there might be benefits beyond relaxation and enjoyment.