According to research from the Mayo Clinic, the major component in green tea-epigallocatechin gallate (EGCG) reduced the number of leukemia cells in patients with chronic lymphocytic leukemia (CLL).

CLL is the second most common type of leukemia in adults. It is a disease of the blood and bone marrow, caused by an excess of certain white blood cells called lymphocytes, are made. Leukemia can sometimes progress slowly, with minimal symptoms.

Mayo clinic tested EGCG, and ran a phase I clinical trial to conclude that the survival of CLL cells was reduced with EGCG. Using the highest dose tested in phase I, they launched a phase II trial with 36 additional patients, making the total of patients 42. Out of the 41 patients who completed the study, 31 percent experienced a 20 percent or greater reduction in blood leukemia count, and 69 percent of the patients who had enlarged lymph dudes saw a reduction of 50 percent or greater.

Doctors Shanafelt and Kay, who were involved in the study, warn patients that the extract is not a substitute for chemotherapy. However, the research sheds light on EGCG used as a means to slow down CLL, as well as researching other nutraceuticals and their impacts on cancer.