For several years, scientists have been investigating the health benefits of tea, particularly unfermented green tea. Interest in the health benefits of one of the world's most popular beverages evolved from a number of epidemiological observations in Asian countries, where green tea is widely imbibed. For example, Chinese men have significantly less prostate cancer than men in most Western countries. In Japan, where smoking rates remain high, lung cancer rates are relatively low. And interestingly, some cohort studies of the women who teach the Japanese tea ceremony have shown that these women die from cancers at strikingly low rates.¹

As with so many food products with antioxidant properties, however, it is extremely hard to tease out the actual effects of green tea consumption. The beverage contains a wide range of chemicals, including caffeine, and it is only one variable including lifestyle, diet and even genetic factors.

Nevertheless, during the last decade, researchers have examined the various constituent components of green tea, particularly substances called flavonoids and polyphenols, which act as powerful antioxidants. In a variety of studies of cells in the laboratory and even in animals, one polyphenol, EGCG or epicallocatechin-3-gallate, has demonstrated anti-cancer activities-preventing cancer cell growth and inducing cell death, particularly in animals.² How EGCG and other polyphenols actually work (they do more than scavenge free radicals) and whether they can serve as reliable chemopreventive substances in humans, however, are still under investigation. Clinical trials testing the effects of green tea consumption among women with breast cancer, supported by the Chemoprevention Branch of the National Cancer Institute, are also underway.³

In the meantime, a cup or two of green tea should cause you no harm. At the very least, it can provide you with an excuse for a relaxing moment during a busy or stressful day.