Green Tea Extract Supplement Review

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Green Tea Extract
  Evaluated for:
Effectiveness Rating Effectiveness Rating
Biopsy-proven pre-cancerous prostate cells (Prostatic Intraepithelial Neoplasia)
+3 (Strong Evidence)
Genital Warts
+2 (Moderate Evidence)


  • Application of green tea extract resulted in the death of cancer cells when tested in the laboratory. Taking green tea extract capsules for one year significantly reduced the number of prostate cells that changed from a pre-cancerous into a cancerous state.
  • The oral dose continued to show benefit for at least one year after the treatments ended.
  • There were and are no known significant side effects.
  • Green tea ointment improves and eliminates both genital and anal warts.
  • This ointment seems at least as effective as current standard medical therapies for genital warts.


  • Whereas green tea extract reduced the risk of cancer in one study, other large studies of populations that drink green tea have not confirmed these results.
  • Future studies are needed to confirm the positive benefits.
  • Most genital warts resolve by themselves in 6-12 months even without any treatment, but using the ointment might speed things along.
  • Green tea ointment can cause some local irritation.
  • Green tea ointment is currently available only by prescription.

Green tea extract does not replace close medical follow-up in individuals at increased risk for prostate cancer or whose biopsies showed pre-cancerous cells. While green tea ointment may heal genital warts faster, the goal of any treatment program should be to prevent sexually transmitted infections. This is best accomplished by the consistent use of barriers, such as condoms. Green tea extract and ointment should not be used in the vagina.

DOSAGE:For biopsy-proven pre-cancerous prostate cells, take 1-2 grams twice daily with meals. For genital warts, apply as directed.

CONCLUSION:Green tea extract is cost effective and seems to be a promising option for men who had prostate biopsies that showed cancerous cells. Although genital warts tend to resolve without treatment, this next-to-nature ointment may speed things along. We conclude that green tea extract is a safe and effective product for biopsy-proven pre-cancerous prostate cells and genital warts. If you use it, remember to tell your doctor and other health care providers.

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Stockfleth, E. et al. Topical Polyphenon E in the treatment of external genital and perianal warts: a randomized controlled trial. British Journal of Dermatology (2008) 158, 1329-1338
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Bettuzzi, S. et al. Chemoprevention of Human Prostate Cancer by Oral Administration of Green Tea Catechins in Volunteers with High-Grade Prostate Intraepithelial Neoplasia: A Preliminary Report from a One-Year Proof-of-Principle Study. Cancer Res (2006) 66(2): 1234-1240
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