Green tea is the most widely used
herbal product, used by 24 to 30 percent of all cancer patients.
Some suggested drinking a large amounts of green tea may improve survival in patients with ovarian cancer. A Chinese study on 254 patients with ovarian cancer evaluated for 3 years in regards to survival and quantity of tea consumed. About 96% of patients were followed at the end of 3 year study period. Statistical analysis were calculated to show a survival difference between tea drinkers and non-drinkers (p<0.001). There were 81 (77.9%) of 104 tea-drinkers who survived to the time of interview, compared to only 67 women (47.9%) still alive among the 140 non-drinkers.
Green tea can interact in a
variety of ways with conventional cancer treatments. The polyphenols in green tea inhibit multiple
cytochrome p450 enzymes that are important in drug metabolism. This enzymes work to degrade chemotherapy and
other toxins that enter our bodies. Consequently, green tea could increase the
plasma concentrations of a variety of chemotherapeutic agents (for example Taxol,
Taxotere, Adriamycin), possibly increasing drug toxicity. On the other hand,
some drug-metabolizing enzymes are induced, which might lead to resistance to
other chemotherapeutic agents.
In addition, preclinical studies
suggest that the polyphenols contained in green tea may inhibit the
induction of tumor cell death by the proteasome inhibitor bortezomib , which is used to treat multiple myeloma.
While it is not clear that patients receiving this drug should refrain from
drinking any green tea, it might be prudent to avoid ingesting large
quantities, until further information is available. Furthermore, do let your doctor know if you
are drinking green tea since it may increase drug toxicities.
Reference:
- Ernst
E, et al. Complementary
and alternative therapies for cancer.
Uptodate. Sept 2012.
- Dy
GK, et al. Complementary and alternative medicine use by patients enrolled onto
phase I clinical trials. J Clin Oncol. 2004;22(23):4810
- Mei
Y, et al. Reversal of cancer multidrug
resistance by green tea polyphenols. J Pharm Pharmacol. 2004;56(10):1307.
Dr. Santoso, thank you for clearing this up. I had read that a lot of green tea can have adverse effects for those of us on chemo, but I didn't really know how to explain it. Many people think that consuming large amounts of green tea will help us. We are all searching for that "magic bullet" and it would be wonderful if something as simple as green tea was it. You have done a great job explaining this.
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