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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.
Published Feb. 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.