The first paragraph of the article, from a website called SciScoop.com, ends thus:
[Tea] could provide a simple and inexpensive way of preventing diabetes and its ensuing complications, including cataracts.
The article refers to research findings published in the Journal of Agriculture and Food Chemistry. In this research, conducted at the University of Scranton, Pennsylvania, researchers found that rats fed green tea had decreased glucose levels and significantly less cataract formation compared to a control group. This difference is probably because high levels of glucose "accelerate diabetic complications such as cataracts."
This is similar to what I reported in the blog posting Dr. Nicholas Perricone on green tea (from The Oprah Winfrey Show).
Someday, perhaps, scientists will find some afflication that green tea doesn't help prevent.