Green tea is high in polyphenols, a class of phytochemicals with 100 times the antioxidant properties of vitamin C.
Catechins, a type of polyphenol, may inhibit the growth of new blood vessels, which some scientists think may help prevent cancer by depriving early tumors of nourishment.
Catechins may also prevent DNA damage caused by carcinogens
Epidemiological studies link daily drinking of green tea daily with a lowered risk of stomach, esophageal and liver cancers.
Consuming 10 cups a day may reduce the risk of heart disease.
Swishing green tea around the mouth like a mouthwash may inhibit cavity-causing bacteria.
According to a study of the skin of laboratory mice, green tea might reduce the incidence of skin cancer.
Black tea is made from the same leaves as green, but is processed differently. Therefore, it could be beneficial too.