Green Tea Gives Oral Cancer the Brushoff

Causes cancer cells to die, study finds

TUESDAY, Dec. 18, 2001 (HealthDayNews) -- In the latest good news on green tea, researchers have found that this Eastern favorite can kill cancer cells in your mouth.

Working with lab cultures, scientists at the Medical College of Georgia's School of Dentistry discovered that the cancer cells die off when exposed to components in the tea, while normal cells are unaffected.

"After 24 hours of incubation, oral cancer cells showed massive programmed cell death," says Stephen Hsu, the lead researcher and an assistant professor of oral biology at the college.

Because no one normally would keep green tea in their mouth for that long a period of time, Hsu tried another experiment, allowing the cells to incubate in green tea polyphenols for two one-hour periods during a day. Polyphenols are antioxidants, chemicals believed to help prevent cancer. The oral cancer cells still died, according to Hsu.

Oral cancer strikes more than 30,000 people every year, and almost a third of them die. It has the worst five-year survival rate of all major cancers, according to the Academy of General Dentistry.

Hsu doesn't know exactly how green tea induces cell death, but he plans to focus future work on answering that question.

"We're trying to make people aware of the benefits of drinking green tea," says Hsu, who believes that the lower oral cancer rates in China have something to do with the consumption of green tea.

Hsu recommends four to six cups of green tea a day for maximum benefit. You don't have to actually drink the tea, swishing it around your mouth will do, he says. But if you do drink the tea, he adds, drink it at a very slow pace so it spends an extended period of time in your mouth.

The study's results will be published in the March/April 2002 issue of the journal General Dentistry.

"Results of this study are encouraging," says Melanie Polk, director of nutrition education for the American Institute for Cancer Research. "But this is just one study."

And, she adds, while numerous studies have shown that green tea offers protection against cancer, other studies that found the opposite to be true.

"The bottom line is that green tea has the potential to be another cancer risk reducer in a mostly plant-based diet," Polk says.

What To Do

For more information on oral cancer and how to prevent it, go to the Academy of General Dentistry.

The benefits of green tea don't stop at your mouth. A study done by the National Cancer Institute found it helped throat cancer and even prostate cancer.

And here's an entertaining history of tea.

SOURCES: Interviews with Stephen Hsu, Ph.D., assistant professor of oral biology, Medical College of Georgia, School of Dentistry, Augusta; Melanie Polk, R.D., director of nutrition education, American Institute for Cancer Research; March/April 2002 General Dentistry
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