e old, the mineral element content is higher than other teas. And the fluorine has the obvious curative effect to against dental caries and the prevention old age osteoporosis; The selenium can stimulate the immunoprotein and the immune body production, strengthens the human body to disease's resistivity, and to treats coronary disease, suppresses the cancer cell the occurrence and the development has the remarkable effect, in the tea the selenium content may reach as high as 3.8~6.4mg/kg. the dark tea is one kind of low caffeine healthy drink (raw material maturity is high, cures and so on factors), compares with may happy as well as other teas, the black tea does not affect the sleep. the aging dark tea in the depositing process, a microorganism experience generation of multiplication and metabolism, has produced a series of not well-known small molecular activity m