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Volume 16, Spring 2004 |
Health
One, two, tea: the simple way to drink yourself to health
Copy Chief
Enjoyed for centuries in such varied places as India , Japan and England, tea is now heralded for its health benefits .
Brewing a kettle of black tea can aid digestion, fight infection and prevent cancer.
Cozying up with some hot chai, cleansing the palate with green tea, or brewing a kettle of black tea can aid digestion, fight infection and prevent cancer. Research has found different panaceas in tea, championing its low caffeine, high antioxidants and beneficial ingredients.
This comes as only a slight surprise to people who have been drinking tea their whole lives. "I have a whole drawer full of different tea bags. I love to try different kinds," said Jaclyn Kosco, an alumna of The College of New Jersey. "My friends exchange our favorite varieties as gifts."
Kosco can attest to the thousands of tea products now available, but in truth, all tea comes from the Camellia sinensis plant, a warm-weather evergreen, which is processed in different ways to create black, oolong and green teas. During oxidation, tea leaves undergo natural chemical reactions that result in distinctive color and taste characteristics. Green tea is not oxidized at all-the leaves are steamed, rolled and dried, while black tea is allowed to oxidize for two to four hours. Oolong tea falls somewhere between green and black teas, in that the leaves are only partially oxidized.
Herbal teas do not come from the Camellia sinensis plant, but are an infusion of leaves, roots, bark, seeds or flowers of other plants. They lack many of the unique characteristics of tea and are not linked to the research that proposes potential health benefits of traditional teas. Recent studies -- such as those from the National Academy of Sciences, the Department of Agriculture and the Food and Drug Administration -- did not include these varieties and, instead, focused on the three traditional teas.
Researchers discovered a chemical in tea that boosts the body's defense against disease fivefold.
According to the Proceedings of the National Academy of Sciences, researchers discovered a chemical in tea that boosts the body's defense against disease fivefold. The report indicates that the chemical prepares cells in the immune system to attack bacteria, viruses and fungi and could, perhaps, be turned into a disease-fighting drug someday.
Authors of the study, which include doctors at Brigham and Women's Hospital in Boston and Harvard Medical School, wrote that five cups of tea a day sharpened the body's defenses against disease. As part of the Brigham study, 11 volunteers drank five cups of tea per day, while 10 others drank coffee. Before the test began, they drew blood samples from all 21 test subjects. The study isolated, from ordinary black tea, a substance called L-thiamine, which the liver breaks down into ethylamine, a molecule that primes the response of an immune blood cell called the gamma-delta T cell.
'We're seeing multiple benefits from tea.'
The researchers cite other studies that show these gamma-delta T cells in the blood are the first line of defense against many types of bacteria, viral, fungal and parasitic infections. Penny Kris-Etherton, a nutrition specialist at Pennsylvania State University, said the Brigham study adds to a growing body of evidence that tea is an effective disease fighter. "This is potentially a very significant finding," she said. "We're seeing multiple benefits from tea."
These results were welcomed by the Tea Association of America, which released a statement saying, "The health effects of tea have been extensively studied. It has been linked to lower heart disease and cancer risk through the action of flavonoids, a type of antioxidant. Other studies have linked tea to helping combat osteoporosis, the brittle bone disease, and to relieving some allergy symptoms."
The association is referring to further evidence released recently that shows the health benefits of holding an afternoon tea. Impartial analysis and hard data are now confirming what the ancients in Asia have known for centuries: tea is good for you.
Those who drink at least 8.5 milliliters (less than half a cup) of green tea each day reduce their risk of breast cancer risk by nearly 30 percent.
According to the Department of Preventive Medicine at the University of Southern California, those who drink at least 8.5 milliliters (less than half a cup) of green tea each day reduce their risk of breast cancer risk by nearly 30 percent.
What's more, scientists with the U.S. Department of Agriculture said they found that consumers who drink black tea for three weeks experience a decrease of 7 percent and 11 percent in their low-density lipoprotein (LDL), or so-called bad cholesterol.
The drink can also have beneficial behavioral effects. Tea is a healthier alternative to other drinks with caffeine, which can have up to four times the amount of caffeine as coffee.
The Food and Drug Administration offers this caffeine comparison per six ounce cup, in milligrams: drip coffee can have as much as 180 mg of caffeine, and two ounces of espresso can have 90 mg; black tea can have 25 to 110 mg, oolong tea can have 12 to 55 mg; green tea can have 8 to 16 mg. Decaf tea has smaller traces of caffeine than decaf coffee: 4 to 6 mg compared to 22 to 45 mg.
Total sales of tea in 2002 were $5.03 billion, up from $1.84 billion in 1990.
With more tea products on the market, and news of its heralded benefits, it's no surprise that, according to the Tea Association of America the U.S.A., total sales of tea in 2002 were $5.03 billion, up from $1.84 billion in 1990.
Catherine E. Galioto, a junior journalism/professional writing major at The College of New Jersey, is the unbound Copy Chief; so if you find any mistakes, please blame her. She is also a freelance writer with several accolades who appears regularly in more than seven publications. Outside of that, things get much harder to define.