Effects of green tea in smokers.




Journal of Nutrition

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Green tea has long been used in much of the world as a popular beverage and a respected medicinal agent. Early Chinese medical literature lists green tea as an agent to promote digestion, improve mental faculties, decrease flatulence and regulate body temperature. The earliest known record of use dates back to around 2700 B.C. Today, ceremonies, celebrations, relaxation time and ordinary meals usually consist of tea in most parts of the world, except where coffee has become the more popular beverage, like the United States. Green tea has antioxidant properties. This means it has the ability to protect against oxidative damage and fight free radicals.

What are free radicals? Everything that exists in the physical world around us--natural or man-made--is held together by chemical bonds. All substances are made of molecules that bond to each other by sharing electrons, the subatomic particles that orbit the atom's nucleus. Electrons like to form pairs; the pairing of electrons creates a biochemical peace and stability, without which, everything would come apart at the seams. Free radicals are molecules that have an unpaired electron. This unpaired electron makes the free radical highly unstable, like a sort of molecular loose cannon. So anxious is the free radical to find a mate for its solitary electron, it will snatch an electron away from whatever is close by. The issue is far from settled at this point, however: you may now have another equally rapacious free radical desperate to replace its stolen electron.

Recently published, a new study has investigated the potential role for green tea in preventing oxidative damage associated with smoking. In this study, 143 heavy smokers received 4 cups daily of green tea, black tea, or water. In this 4-month intervention, only 133 participants completed this trial. Researchers measured oxidative damage through a specific urinary test. After analyzing the test results, only those who drank the green tea had decreased levels of a chemical component associated with oxidative damage. There were no changes seen in those drinking black tea or water. The authors of this study concluded that, “regular green tea drinking might protect smokers from oxidative damages and could reduce cancer risk or other diseases caused by free radicals associated with smoking.”1


1. Hakim IM, et al. Effect of Increased Tea Consumption on Oxidative DNA Damage among Smokers: A Randomized Controlled Study. J Nutr. Oct 2003;133(10): 3303S-3309S.