Oodles of antioxidants are contained in green tea, black tea, even oolong tea.
By Jeanie Lerche Davis
WebMD Weight Loss Clinic - Feature
Reviewed By Brunilda Nazario, MD
Read the tea leaves, caffeine lovers. Tea is gaining ground over coffee. Tearooms are popping up everywhere. Even Starbucks is bucking up its tea menu.
The health benefits of tea are one compelling reason: Green and black teas have 10 times the antioxidants found in fruits and veggies, by one estimate.
For jaded coffee drinkers, tea also offers new sensory frontiers, with its roots in Chinese, Japanese, Indian, African, and South American cultures.
When you sip a chai tea latte, for example, you're enjoying a beverage born in India. "All over India, on almost every street corner, vendors sell chai tea," says Joe Simrany, president of the Tea Council of the U.S.A.
"The traditional tea lover won't like chai tea that much," he tells WebMD. "The spices -- ginger, cardamom -- overpower the taste of the black tea. But for American coffee consumers, it's perfect."
In the U.S., elegant tea salons, tearooms, and take-out tea shops are popping up everywhere, says Simrany. "Four years ago, we had one-quarter the tea salons we have today. Even coffee shops are selling more tea."
People find tranquility in tearooms, says Dominique Tanton, manager of the Dushanbe Teahouse, an exquisite traditional Persian teahouse in Boulder, Colo.
"Coffee shops are for the quick caffeine buzz before work or while you're frantically studying for a test," she tells WebMD. "A tearoom is for slowing down, relaxing, admiring the surroundings."
Studies of humans, animals, and Petri dish experiments show that black and green tea is highly beneficial to our health, says 82-year-old John Weisburger, PhD, senior researcher at the Institute for Cancer Prevention in Valhalla, N.Y.
"I've published over 500 papers, including a helluva lot on tea," says Weisburger, who drinks 10 cups daily. "I was the first American researcher to show that tea modifies the metabolism to detoxify harmful chemicals."
Green tea, black tea, oolong tea -- they all come from the same tea plant, Camellia sinensis; the leaves are simply processed differently, explains Weisburger. Green tea leaves are not fermented; they are withered and steamed. Black tea and oolong tea leaves undergo crushing and fermenting processes.
All teas from the Camellia tea plant are rich in polyphenols, which are antioxidants -- meaning they scavenge for cell-damaging free radicals and detoxify them, says Weisburger.
"Astounding" aptly describes tea's antioxidant power: "Whether it's green or black, tea has about 8 to 10 times the polyphenols found in fruits and vegetables," he says.
While herbal teas may also contain antioxidants, less is known about them, Weisburger adds.
"In my lab, we found that green and black tea had identical amounts of polyphenols," he tells WebMD. "We found that both types of tea blocked DNA damage associated with tobacco and other toxic chemicals. In animal studies, tea-drinking rats have less cancer."
Look at the world's big tea-drinkers, like Japan and China. "They have much less heart disease and don't have certain cancers that we in the western world suffer," says Weisburger.
However, be careful about doctoring-up your tea, says Weisburger. One study found that adding too much milk to can greatly reduce tea's health benefits.
"The scientific evidence about tea is evolving and I think it's compelling," Jeffrey Blumberg, PhD, Friedman School of Nutrition Science and Policy of Tufts University, tells WebMD.
The Evidence on Tea
Tea is a great example of the past decade's research of antioxidants, he says. "There is a pretty consistent body of evidence suggesting there is a benefit to tea. Tea is a very rich source of a specific kind of antioxidant -- flavonoids," says Blumberg.
Admittedly, there has been conflict among the studies. One large study in the American Journal of Clinical Nutrition followed nearly 40,000 women for nearly seven years. Researchers found that drinking over four cups of tea a day did nothing to reduce their risk of heart disease.
However, the bulk of research is what counts most, Blumberg says. And that research has found that regular tea drinkers -- people who drink two cups or more a day -- have less heart disease and stroke, lower total and LDL cholesterol, and that they recover from heart attacks faster.
Smokers who drink four cups of tea regularly have less evidence of DNA cell damage -- genetic mutations that can lead to cancer. Mouse studies have found fewer lung tumors in mice drinking tea.
When tea drinkers' immune cells are exposed to germs in a Petri dish, the immune cells spring into action. When coffee drinkers' immune cells are exposed to germs, nothing happens.
Laboratory tests have also shown that black and green tea may help boost metabolism to aid weight loss, block allergic response, slow the growth of tumors, protect bones, fight bad breath, improve skin, protect against Parkinson's disease, even delay the onset of diabetes.
How is this possible? While the mechanisms within tea are complex, it seems to be the detoxifying effect of antioxidants that protects cells from free radicals -- the damage that leads to blood clot formation, atherosclerosis, and cancer, says Weisburger.
However, tea is not a cure-all. "Tea is certainly not a panacea," Blumberg tells WebMD. In fact, not everyone may benefit equally from tea. "I think we need to do more work to better define both why and who benefits from tea consumption."
The Bottom Line
"If you want do something good for yourself, drink tea," says Blumberg. "It has no calories and lots of phytochemicals. If you're drinking tea, you're not drinking soda -- that's a real benefit. Water doesn't give you those phytochemicals."
Weisburger recommends drinking six to 10 cups of black or green tea throughout the day, starting with breakfast. Switch to decaf tea midday, if you need to. "Flavonoids are unchanged by removal of caffeine," he says.
Kids should drinking tea, too. "We try to get children eat vegetables," Weisburger say. "I'm suggesting that children age 6 on should be drinking decaffeinated tea."
Not that kids need a fancy tearoom -- iced tea at home works fine.
February 9, 2004.
SOURCES: John Weisburger, PhD, senior researcher, Institute for Cancer Prevention, Valhalla, N.Y. Joe Simrany, president, Tea Council of the U.S.A. Dominique Tanton, Dushanbe Teahouse, Boulder, Colo. WebMD Medical News: "Tea Good for Heart Disease, Cancer." WebMD Medical News: "Tea Extract Can Lower Cholesterol." WebMD Medical News: "There's Something to Be Said for Having 'Tea Bones.'" WebMD Medical News: "Tea Prolongs Survival After Heart Attack." WebMD Medical News: "Health Benefit of Tea: Add Germ Fighting." WebMD Medical News: "Green Tea, Allergy Fighter?" WebMD Medical News: "Tea Fights Bad Breath, Mouth Bacteria." WebMD Medical News: "Green Tea Protects Against Parkinson's." WebMD Medical News: "Green Tea Supplement May Delay Diabetes." WebMD Medical News: "Green Tea Boosts Metabolism, Protects Against Diseases." WebMD Medical News: "Green Tea, White Tea Fight Colon Cancer." WebMD Medical News: "Tea: A Healthy Brew." WebMD Medical News: "Green Tea, Glycine May Slow Tumor Growth." Sesso, H. American Journal of Clinical Nutrition, June 2003; vol 77: pp 1400-1408. Hodgson, J. American Journal of Clinical Nutrition, September 2003; vol 133: pp 2883-2886.
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