Tea, a beverage made from the leaves of the evergreen shrubCamellia sinensis, is primarily manufactured as green, black, oolong or white, with green tea representing approximately 20% of the tea products consumed. Green tea contains many polyphenol compounds, with epigallocatechin gallate (EGCG) being the most prominent. These polyphenols have been shown to exhibit a chemopreventive effect against several cancers in vitro andin vivo (Yang, 2002). In addition, both green and black teas contain high levels of antioxidants—even more than most vegetables and fruits (Paganga, 1999;Prior, 1999). The antioxidant activities of 2 cups of tea are equivalent to 4 apples, or 7 glasses of orange juice, or 20 glasses of apple juice (Paganga, 1999).