After a year’s oral administration of green tea catechins (GTCs), only one man in a group of 32 at high risk for prostate cancer developed the disease, compared to nine out of 30 in a control, according to a team of Italians led by Saverio Bettuzzi, PhD.

“Numerous earlier studies, including ours, have demonstrated that green tea catechins, or pure EGCG (a major component of GTCs), inhibited cancer cell growth in laboratory models,” Bettuzzi explained. “We wanted to conduct a clinical trial to find out whether catechins could prevent cancer in men. The answer clearly is yes.”

To gauge susceptibility for prostate cancer among their research subjects, the team of Italian scientists recruited men with high-grade prostatic intraepithelial neoplasia – premalignant lesions that presage invasive prostate cancer within one year in nearly a third of cases and for which no treatment was given.

Of the 62 volunteers, 32 received three tablets per day of 200 mg each GTCs; the remainder were given a placebo. Follow-up biopsies were administered after six months and again at one year. Only one case of prostate cancer was diagnosed among those receiving 600 mg daily of GTCs, while nine cases were found in the untreated group. The 30% incidence rate among controls is consistent with previous findings, as was the absence of significant side effects or adverse reactions.

American Association for Cancer Research, Apr 20, 2005