It's Not Queasy Being Green

Green tea may protect stomach from severe upset

MONDAY, May 21, 2001 (HealthDayNews) -- Forget about Earl Grey and say no to orange pekoe. If you want your morning beverage to fight stomach disorders, a new study says the color of your cup of tea should be green.

The study of residents of a Chinese island is the first to link green tea to the rate of gastritis, a stomach inflammation that can lead to cancer.

But the researchers aren't sure how much green tea you should drink, while other recent studies question whether it does any good at all.

Those doubts don't stop Dr. Zuo-Feng Zhang, co-author of the latest study, from downing several cups of green tea daily. "We see a very strong protective effect," says Zhang, a professor of epidemiology at the University of California at Los Angeles School of Public Health,

Green and black tea come from the same plants, but green tea doesn't go through a fermentation process that removes chemicals that may be beneficial, Zhang says.

American and Chinese experts studied how much green tea was consumed by 133 stomach cancer patients, 166 patients with colonic gastritis and 433 people with no stomach disease.

Zhang and his colleagues adjusted for risk factors that can cause stomach problems, such as smoking, alcohol use, high intake of salt and diets low in fruits and vegetables.

They found that people who drank one to three cups of green tea daily had a 30 percent lower rate of stomach cancer. Those who drank more than three cups had a 61 percent lower rate. The findings are reported in the May International Journal of Cancer.

Green tea drinkers also had lower rates of gastritis. Those who had been green tea drinkers for one to 13 years had a 25 percent lower rate of the disease; those who drank the beverage for more than 13 years had a 66 percent lower rate.

Zhang says antioxidants in green tea may fight cancer. The antioxidants target "free radicals," harmful byproducts released when cells convert food to energy.

Green tea also may prevent inflammation in the stomach, which appears to be a factor in cancer development, says another expert, Dr. Robert A. Newman, a professor at Houston's M.D. Anderson Cancer Center.

But other studies question any link between stomach cancer and green tea.

One of the most recent studies, published in the March 1 issue of The New England Journal of Medicine, found no link between green tea -- or coffee or black tea -- and stomach cancer rates in a region of Japan.

Newman says the difficulties of studying green tea may explain the different study results. He says it's hard to tell how much green tea people consumed and whether risk factors for stomach disease play a role in making some people sick.

Newman is studying the effects of extracts of green tea in a pill form. He hopes to find out if the green tea pills will prevent head and neck cancer.

What To Do

A few cups a day of green tea shouldn't hurt you, but watch out if you're sensitive to caffeine. Some people in Newman's preliminary study reported nervousness and insomnia, signs they were getting too much caffeine.

Also, green tea does not always sit well on American taste buds. Some says it tastes like boiled grass. Experts recommend trying a flavored brand or using plenty of milk and sugar. You could also try iced green tea, which is available on some grocery store shelves.

To see what clinical trials are available for gastrointestinal problems, check Veritas Medicine or the National Institutes of Health. has an information sheet about green tea.

Also, this fact sheet written by British tea manufacturers explains the differences between green and black tea.

And read previous HealthDay articles on the health effects of tea.

SOURCES: Interviews with Dr. Zuo-Feng Zhang, M.D., Ph.D., professor of epidemiology, University of California at Los Angeles School of Public Health; Dr. Robert Newman, M.D., professor of pharmacology and medicine, M.D. Anderson Cancer Center, Houston; May 2001 International Journal of Cancer
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