A small study of men with advanced prostate cancer revealed that green tea had no therapeutic effect.

Previous studies have suggested that green tea might have some benefit in prostate cancer. The therapeutic components are believed to be compounds called polyphenols, which are especially abundant in green tea.

Lab studies have shown that prostate cancer cells are killed off by polyphenols, and that green tea shrinks prostate tumors in animals. In a new study, researchers at the Mayo Clinic gave a high dose - six grams a day - of green tea to a group of 42 men with advanced prostate cancer. The men had the tea either hot, iced or in juice. Unfortunately, no benefit could be detected after a month - save that prostate specific antigen (PSA) levels dropped temporarily in one man. PSA levels are used as a 'marker' of tumor progress.

Green tea does not, then, show the hoped for anti-cancer effect in men with advanced cancer. More work is needed to see whether it can prevent cancer, or have benefits at an earlier stage of the disease.

Source

Cancer 15th March 2003