Written by Jianping Liu, Xun Li and the CAM-Cancer Consortium.
Updated May 8, 2012

Green tea (Camellia sinensis)

Abstract and key points

  • Green tea is derived from the schrub Camellia Sinensis through a non-fermenting process.
  • The evidence for an association between green tea consumption and the incidence of cancer is generally inconsistent.
  • Drinking green tea appears safe at regular, habitual and moderate use.

Green tea is derived from the shrub Camellia sinensis, the same plant as used for black tea, but is not fermented.

A total of 12 systematic reviews and/or meta-analyses investigated the association between green tea consumption and the risk of cancer in general or specific cancer types including ovarian, prostate, liver, stomach, colorectal, breast and lung cancer. Although the majority of reviews found an inverse association, the findings of both cohort and case-control studies are still inconclusive.

Drinking green tea appears safe at regular, habitual and moderate use (3-9 cups per day).

Citation

Jianping Liu, Xun Li , CAM-Cancer Consortium. Green tea (Camellia sinensis) [online document]. http://www.cam-cancer.org/CAM-Summaries/Herbal-products/Green-tea-Camellia-sinensis. May 8, 2012.

Document history

Summary last updated and revised in May 2012 by Jianping Liu and Xun Li.
Summary fully updated and revised in April 2012 by Jianping Liu and Xun Li.
Summary first published in September 2005, authored by Jianping Liu.

References

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