(HealthDay News) -- Substances found in green tea work their way into the tissues of the eye and could protect against common eye diseases like glaucoma, researchers say.

The findings, published in the current issue of the Journal of Agricultural and Food Chemistry, suggest that the substances, known as catechins, are absorbed by the lens, retina and other parts of the eye. Catechins are antioxidants thought to protect the body against damage from oxygen.

According to Chi Pui Pang and colleagues from the department of ophthalmology and visual sciences at the Chinese University of Hong Kong, it wasn't known if catechins make their way from the mouth to the gastrointestinal system to the eyes.

The study authors gave green tea to rats and then tested their eyes to see if catechins affected them. They did, reducing oxidative stress in the eye for up to 20 hours.

"Our results indicate that green tea consumption could benefit the eye against oxidative stress," the authors said.

More information

The National Library of Medicine has more on green tea.