Tea
Looks Promising As Cancer Fighter
Antioxidant
Found In Grapes Has Limited Effect
Green and black
tea can slow down the spread of prostate cancer, while a highly touted
antioxidant found in red wine, grapes, and peanuts does not perform
well as a cancer preventive, two new studies have found.
In Dr. Henning's
study was presented at the Experimental Biology 2004
meeting in Washington, D.C.
For the tea
study, Dr. Susanne Henning, an associate researcher at the Center for
Human Nutrition at UCLA's David Geffen School of Medicine, assigned
20 men, all scheduled for prostate removal due to cancer, to drink either
black tea, green tea, or soda - five cups a day for five days before
surgery.
Prostate Cancer
Growth Slowed By Tea
The aim was
to see if substances called polyphenols found in tea might slow prostate
cancer cell growth. Other researchers have found these polyphenols induce
death in cancer cells.
In Dr. Henning's
study, tissue from each man's prostate was removed during the surgery
and given to a pathologist, who then turned it over to the researchers
for evaluation.
When they looked
at the proliferation of prostate cancer cells in the sample of tissue
removed, there was a decrease in how fast new cancer cells appeared
for men who had consumed either black or green tea. The same was not
found in those who drank the soda.
"This is the
first human study to show that EGCG (epigallocatechin gallate, a polyphenol
in the tea) shows up in the prostate after drinking tea," says Dr. Henning,
"Black tea is a bit better. This strengthens the idea that green tea
and black tea help prevent prostate cancer."
For several
years, researchers have focused on tea and its potential to prevent
cancer, partly because in parts of the world where tea is consumed,
the incidence of some cancers is lower.
Grape
Substance Less Promising
The other study,
presented at the same meeting, looked at the cancer-fighting ability
of resveratrol, a dietary polyphenol, and did not produce the same promising
results.
For several
years, resveratrol has been discussed as a natural way to protect against
both cancer and heart disease. But it is not known if dietary resveratrol
will actually reach the proposed sites of action, said study author
Dr. Thomas Walle, a professor of pharmacology at the Medical University
of South Carolina, Charleston.
Oral dietary
supplements of resveratrol are not likely to have any effect on breast
and prostate cancer, Dr. Walle concluded after his study. He gave resveratrol
both by mouth and intravenously to six healthy volunteers. Then they
looked for resveratrol in the blood samples drawn later.
Only trace amounts
reached the bloodstream, Dr. Walle says. "We are not trying to disclaim
anything, but rather to answer a very basic question that is being asked
by the drug industry all the time," he says. "When they introduce
a new drug, they ask, 'Will it get into the circulation?'"
"It has been
claimed that resveratrol may prevent breast or prostate cancer, and
that may not be the case," Dr. Walle says.
Even though
the bloodstream had only trace amounts of resveratrol, Dr. Walle says
he has found in other studies that resveratrol does accumulate in ephithelial
cells along the digestive tract, "So it could prevent cancer in those
cells."
Dr. Henning
says her findings are too premature to recommend that men drink black
or green tea in hopes of preventing prostate cancer.
Dr. Herman Kattlove,
a spokesman for the American Cancer Society, agrees.
"It's a long distance from this data to any possible clinical effect,"
he says.
Instead of focusing
on single supplements or substances, Dr. Kattlove suggests boosting
fruit and vegetable intake.
"Eating more
fresh fruits and vegetables is protective from cancer," he says, adding
it is highly unlikely a single substance in the foods provides the effect.
Always consult
your physician for more information.
|
June 2004
Tea
Looks Promising As Cancer Fighter
Prostate
Cancer Growth Slowed By Tea
Grape
Substance Less Promising
What
Is Complementary and Alternative Medicine
Online
Resources
Other
Resources:
Find
a St. John's Mercy Physician
St.
John's Mercy Center for New Health Options
Eye
Health Information
St.
John's Mercy Classes and Programs
What Is
Complementary and Alternative Medicine
The
term complementary and alternative medicine (CAM) encompasses nonconventional
approaches to healing, beyond traditional medicine.
Complementary
medicine is any form of therapy used in combination with other alternative
treatments or standard/conventional medicine.
Complementary
therapy usually serves to relieve symptoms and improve quality of life.
Alternative
medicine is used alone, without recommended standard treatment.
Some
people use complementary treatments to relieve symptoms or side effects
while undergoing standard/conventional treatment (such as pain relief
during cancer treatment).
Standard/conventional
medicine refers to medical treatments that have been scientifically
tested and found to be safe and effective.
The
standard or conventional treatments have been approved by the US
Food and Drug Administration (FDA).
Other
people may decide to pursue either complementary or alternative therapy.
It
is highly recommended that you consult your physician before beginning
any treatment regime, as these treatments are not scientifically tested
or proven.
Always
consult your physician for more information.
Online
Resources
American
Cancer Society
Centers
for Disease Control and Prevention (CDC)
National
Cancer Institute
National
Institutes of Health (NIH)
National
Library of Medicine
US
Department of Heath and Human Services
US
Food and Drug Administration
|
