Substances found in green tea could help fight eye disease, according to authors of the latest research from the University of Hong Kong.

Scientists confirmed that substances found in green tea - already known for their powerful disease-fighting properties - do penetrate into the tissues of the eye. Scientists were previously unsure if catechins, which are antioxidants thought to protect the body against damage from oxygen, could make their way from the mouth to the gastrointestinal system to the eyes. This suggests that green tea offers protection against common eye diseases.

Catechins, phytochemical compounds that are found predominately in green tea, as well as other antioxidants such as Vitamin C and E, lutein and zeaxanthin have long been linked with having the capability of protecting the eye from disease, but this is the first study to prove this theory. It explains how the lens, retina and other tissues within the eyes absorb these beneficial substances. It also adds to green tea's long list of already documented health benefits that it also helps to protect against common eye diseases such as glaucoma.

Study Details

The study was conducted using laboratory rats that were fed green tea over a period of time. Subsequent dissection and analysis of the rats' eye tissue showed significant absorption of individual catechins into various structures of the eye. The retina was seen to absorb the highest levels of gallocatechin, with the aqueous humor absorbing epigallocatechin, both benefical antioxidants.

The effect of the green tea catechins on the laboratory rats was a reduction in harmful oxidative stress in the eye, which lasted up to twenty hours. The authors of the research stated that their "results indicate that green tea consumption could benefit the eye against oxidative stress".

Research Paper details:

Chu et al. Green tea Catechins and Their Oxidative Protection in the Rat Eye. Journal of Agricultural and Food Chemistry, 2010; 58 (3): 1523.