ken.w

Green Tea May Offer Some Protection from Breast Cancer
Library: MED
Keywords: BREAST CANCER, GREEN TEA
Description: Researchers from Boston University Schools of Medicine and
Public Health have shown that compounds found in green tea may offer some
protection from development of breast cancer. (J of Cellular Biochemistry,
Jul-2001)

GREEN TEA MAY OFFER SOME PROTECTION FROM BREAST CANCER

Boston, MA-Researchers from Boston University Schools of Medicine and Public
Health have shown that compounds found in green tea may offer some
protection from development of breast cancer. The study, which appears in
the July 2001 issue of Journal of Cellular Biochemistry, is the first study
to report significant reduction in the size and malignancy of breast tumors
in rats drinking green tea compared to rats drinking water.

The researchers, led by Gail Sonenshein, MD, a professor of biochemistry,
and Adrianne Rogers, MD, a professor of pathology at Boston University
School of Medicine, compared breast cancer development in the 2 groups of
female rats. They found that the rats given green tea developed their tumors
later than rats drinking water (averaging 88 days as compared to 66 days),
and also had a 70% reduction in tumor weight compared to those receiving
water. Lastly, the green tea group had less invasive cancers than the
water-fed group.

According to the researchers, statistics indicate that the incidence of
breast cancer in regions where green tea is consumed in large quantities,
notably China and Japan, is much lower than in western societies. "There
are, of course, many dietary and other differences to be examined, but green
tea is considered one of the prime candidates to account for this
difference. Although we don't believe green tea by itself will prevent
breast cancer, it may prove beneficial when used in combination with other
dietary factors," added Sonenshein.


Green Tea Linked to Reduced Breast Cancer Risk


By Suzanne Rostler


NEW YORK, Jul 18 (Reuters Health) - Compounds in green tea may help protect
women against breast cancer, preliminary study findings suggest.


Investigators found that rats who drank water containing green tea had
reductions in the size and malignancy of breast tumors compared with rats
that drank only water. Additionally, the tumors of tea-drinking rats
developed later and were less invasive.


While more research needs to be conducted, the findings, coupled with
observations of lower rates of breast cancer in countries where green tea is
consumed daily, suggest that green tea may benefit women as part of an
overall healthy diet.


"I know of no major detrimental side effects when consuming 3 to 5 cups of
green tea per day. Thus, I see no problems in drinking green tea now for
prevention," Dr. Gail Sonenshein, the study's lead author, told Reuters
Health.


Although data from animal studies cannot always be generalized to humans,
the findings "suggest that green tea can be protective against breast cancer
induced by environmental carcinogens," added Sonenshein, a professor of
biochemistry at the Boston University School of Medicine and Public Health
in Massachusetts.


However, patients who are undergoing radiation or chemotherapy for breast
cancer should consult with their doctors before drinking large amounts of
green tea, she noted.


According to the report in the July issue of the Journal of Cellular
Biochemistry, polyphenols, compounds that are abundant in green tea, red
wine and olive oil, may protect against various types of cancer. Polyphenols
are potent antioxidants, compounds that help neutralize disease-causing free
radicals. These cell-damaging molecules occur naturally in the body and are
linked with heart disease, aging and a number of other disorders.


Dry green tea leaves, which are about 40% polyphenols by weight, may also
reduce the risk of cancer of the stomach, lung, colon, rectum, liver and
pancreas, study findings have suggested.


Breast cancer is the second-leading cause of cancer death among US women,
according to the American Cancer Society.


SOURCE: Journal of Cellular Biochemistry July 2001.

Mechanistic findings of green tea as cancer preventive for humans.

Fujiki H, Suganuma M, Okabe S, et al. Proc Soc Exp Biol Med
1999;220:225-228.

Based on our initial work with green tea, in which repeated topical
applications of (-)-epigallocatechin gallate (EGCG), the main green tea
polyphenol, inhibited tumor promotion in a two-stage carcinogenesis
experiment on mouse skin (Phytother Res 1, 44-47, 1987), numerous scientists
have since provided so much additional evidence of the benefits of drinking
green tea that it is now an acknowledged cancer preventive in Japan, and
will possibly soon be recognized as such in other countries. Our work has so
far produced several important results with EGCG and green tea: a wide range
of target organs in animal experiments for cancer prevention, wide
bioavailability of 3H-EGCG in various organs of mice, delayed cancer onset
of patients with a history of consuming over 10 cups of green tea per day,
and absence of any severe adverse effects among volunteers who took 15 green
tea tablets per day (2.25 g green tea extracts, 337.5 mg EGCG, and 135 mg
caffeine) for 6 months. This paper introduces three new findings: 1) EGCG
interacted with the phospholipid bilayer membrane resulting in confirmation
of the sealing effect of EGCG; 2) EGCG inhibited TNF-alpha gene expression
in the cells and TNF-alpha release from the cells; 3) high consumption of
green tea was closely associated with decreased numbers of axillary lymph
node metastases among premenopausal Stage I and II breast cancer patients,
and with increased expression of progesterone and estrogen receptors among
postmenopausal ones. These results provide new insights into our
understanding of the mechanisms of action of tea polyphenols and green tea
extract as a cancer preventive

i_never_tan

I really should try the green tea again. In this part of Connecticut
where I live, a recent study showed we have a high incidence of breast
cancer. I don't know what is going on, but when you read the obits,
their are many young deaths, including men. Nora

mel

Hiya,
what is the difference between green and "normal" tea? Is it just the newer
leaves? Do you drink it it like fruit teas or do you add milk?
Thanks
Mel :-)


confirmation

expression

patients,

among


tea

gary r. schmidt

The difference is to do with how the leaves are treated after they have
been picked. Green tea and black tea have similar levels of caffeine
and so forth, it's another thing again to change such constituents.

Goggle for "green tea production methods" and "black tea production
methods" and you'll be a pocket expert in no time :-)

Cheers,
Gary B-)
--
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