The secret of green tea lies in the fact it is rich in catechin polyphenols, particularly epigallocatechin gallate (EGCG). EGCG is a powerful anti-oxidant: besides inhibiting the growth of cancer cells, it kills cancer cells without harming healthy tissue. It has also been effective in lowering LDL cholesterol levels, and inhibiting the abnormal formation of blood clots. The latter takes on added importance when you consider that thrombosis (the formation of abnormal blood clots) is the leading cause of heart attacks and stroke.
Marji McCullough, ScD, RD, the American Cancer Society's strategic director of nutritional epidemiology, says human studies haven't yet proven what researchers like Chan have discovered in the lab: green tea's EGCG regulates and inhibits cancer growth and kills cells that are growing inappropriately.