Researchers at the Mayo clinic originally showed that epigallocatechin-3-gallate (EGCG) in green tea had a significant effect on leukaemia claiming it could stop the disease in its tracks by interfering with crucial communication signals. Four to ten cups of green tea per day seems the appropriate level.
In 2009 they have taken this further with Clinical Trials. In phase I they showed an extract from Green tea, Polyphenon E, actually slowed CLL growth and stopped lymph node swelling (Journal of Clinical Oncology).
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