Green tea leaves come from the plant Camellia sinensis (1). What differentiates green tea from black and oolong is not the type of plant, but instead it is the degree of fermentation of the leaves. Black tea is fermented but oolong tea is only partially fermented and green tea is not fermented (2). Green tea contains polyphenols and catechin flavanols such as epigallocatechin gallate (EGCG), epicatechin gallate (ECG), epigallocatechin (EGC), epicatechin (EC), which make up about