Treatment Snapshot
March 24, 2010
Excerpt from "Only 10 Seconds to Care"
December 23, 2009 – Wendy Harpham, MD
Cancer as a Turning Point
December 23, 2009 – Don Vaughan
Best Face Forward
December 23, 2009 – Lacey Meyer
Recipes from Chef Hans Rueffert
December 20, 2009
A Skinny Chef You Can Trust
December 22, 2009 – Karen Patterson
Getting Help
December 23, 2009 – Jo Cavallo
Stress Reducers
December 23, 2009 – Laurie M. Fisher
Cisforcupid.com
December 23, 2009 – Lacey Meyer
Only 10 Seconds to Care: Help and Hope for Busy Clinicians
December 23, 2009 – Kathy LaTour
Flavored-Cigarette Ban Takes Effect, With More to Come
December 23, 2009 – Lacey Meyer
Stress, Depression & PTSD
December 23, 2009 – Laurie M. Fisher
Imaging Strategies: The Bigger Picture
December 23, 2009 – Laura Beil
Herceptin Combinations Improve Survival, Lessen Heart Toxicity
December 23, 2009 – Laura Beil
Integrative Techniques: A Sampler
December 23, 2009 – Marc Silver
Drug Therapies
December 23, 2009 – Elizabeth Whittington
Letters from Our Readers
December 23, 2009
Treatment Updates
December 23, 2009 – Staff Reports
CDC picks up the tab for colon cancer screening
December 23, 2009 – Lacey Meyer
Mutant Tissue Wanted
December 23, 2009 – Kathy LaTour
The More You Know
December 23, 2009 – Helen Osborne
Patients' Songs Take Flight
December 23, 2009 – Bunmi Ishola
Q&A: Cervical Cancer Vaccine
December 23, 2009 – Len Lichtenfeld, MD
Comfort in Strange Places
December 23, 2009 – Susie Kasinski Drummond
The 'Price' is $1 Million
December 23, 2009 – Lacey Meyer
Pancreatic Cancer Symposia
December 23, 2009
Tired of Being Tired?
December 23, 2009 – Lacey Meyer
Message From the Editor
December 23, 2009 – Debu Tripathy, MD
Beneficial Brew
December 23, 2009 – Lena Huang
Gut Reaction
December 23, 2009 – Karen Patterson
Today's Lesson: Cancer
December 23, 2009 – Bunmi Ishola
Uncertain Obligations
December 23, 2009 – Jo Cavallo
Beyond Face Value
December 22, 2009 – Terry Healey
Cancer's Silver Lining
December 22, 2009 – Don Vaughan
Kids Allowed
December 21, 2009 – Marc Silver
Layman's Terms
December 23, 2009 – Charlotte Huff
All Stressed Out
December 23, 2009 – Laurie M. Fisher
Bad Neighbors
December 22, 2009 – Laura Beil
Treatment Snapshot
March 24, 2010
Excerpt from "Only 10 Seconds to Care"
December 23, 2009 – Wendy Harpham, MD
Cancer as a Turning Point
December 23, 2009 – Don Vaughan
Best Face Forward
December 23, 2009 – Lacey Meyer
Recipes from Chef Hans Rueffert
December 20, 2009
A Skinny Chef You Can Trust
December 22, 2009 – Karen Patterson
Getting Help
December 23, 2009 – Jo Cavallo
Stress Reducers
December 23, 2009 – Laurie M. Fisher
Cisforcupid.com
December 23, 2009 – Lacey Meyer
Only 10 Seconds to Care: Help and Hope for Busy Clinicians
December 23, 2009 – Kathy LaTour
Flavored-Cigarette Ban Takes Effect, With More to Come
December 23, 2009 – Lacey Meyer
Stress, Depression & PTSD
December 23, 2009 – Laurie M. Fisher
Imaging Strategies: The Bigger Picture
December 23, 2009 – Laura Beil
Herceptin Combinations Improve Survival, Lessen Heart Toxicity
December 23, 2009 – Laura Beil
Integrative Techniques: A Sampler
December 23, 2009 – Marc Silver
Drug Therapies
December 23, 2009 – Elizabeth Whittington
Letters from Our Readers
December 23, 2009
Treatment Updates
December 23, 2009 – Staff Reports
CDC picks up the tab for colon cancer screening
December 23, 2009 – Lacey Meyer
Mutant Tissue Wanted
December 23, 2009 – Kathy LaTour
The More You Know
December 23, 2009 – Helen Osborne
Patients' Songs Take Flight
December 23, 2009 – Bunmi Ishola
Q&A: Cervical Cancer Vaccine
December 23, 2009 – Len Lichtenfeld, MD
Comfort in Strange Places
December 23, 2009 – Susie Kasinski Drummond
The 'Price' is $1 Million
December 23, 2009 – Lacey Meyer
Pancreatic Cancer Symposia
December 23, 2009
Tired of Being Tired?
December 23, 2009 – Lacey Meyer
Message From the Editor
December 23, 2009 – Debu Tripathy, MD
Currently Viewing
Beneficial Brew
December 23, 2009 – Lena Huang
Today's Lesson: Cancer
December 23, 2009 – Bunmi Ishola
Uncertain Obligations
December 23, 2009 – Jo Cavallo
Beyond Face Value
December 22, 2009 – Terry Healey
Cancer's Silver Lining
December 22, 2009 – Don Vaughan
Kids Allowed
December 21, 2009 – Marc Silver
Layman's Terms
December 23, 2009 – Charlotte Huff
All Stressed Out
December 23, 2009 – Laurie M. Fisher
Bad Neighbors
December 22, 2009 – Laura Beil

Beneficial Brew

Can green tea prevent cancer?

BY Lena Huang
PUBLISHED December 23, 2009

For centuries, green tea has been a common drink in Asian countries. But with claims of its health benefits flourishing today, green tea is ­common not only as a beverage, but also in products you wouldn’t expect, such as yogurt, cookies, and sodas.

A recent review, published by The Cochrane Database of Systemic Reviews, looked at 51 studies of green tea consumption and its effect on a variety of cancers, including breast, prostate, lung, oral, and digestive tract. Although some studies showed a decreased risk for prostate cancer in men, other studies were contradictory. The authors concluded there was “insufficient and conflicting evidence” to recommend green tea as chemoprevention; however, drinking a cup or two of green tea a day appears to be safe. 

And yet, it may not be safe for everyone. In June, a study published in the journal Blood found that EGCG may counteract the effects of Velcade (bortezomib), an approved treatment for multiple myeloma and mantle cell lymphoma. In the study, high concentrations of EGCG (obtained by two to three capsules of green tea extract supplements) blocked Velcade’s antitumor effect, suggesting that patients on Velcade should avoid green tea products. 

Faced with food manufacturers who want to put claims of green tea’s health benefits on food labels, in 2005 the Food and Drug Administration came out with its own conclusion that, although green tea is a safe substance in moderation, it is unlikely to reduce the risk of cancers based on current data. 

However, last July, the FDA granted orphan drug designation, which provides incentives for pharmaceutical companies to develop treatments for rare diseases, to the botanical drug Polyphenon E for the treatment of chronic lymphocytic leukemia. Polyphenon E’s primary ingredient is EGCG extracted from green tea leaves. A phase 2 trial is currently under way, testing the agent’s effectiveness in CLL patients taking a daily oral dose.

Currently, there are more than 20 clinical trials examining green tea and its effect on cancer. So until more conclusive evidence emerges, Yuan and Wu agree that in moderation (one to two cups a day) green tea is not harmful and may, one day, prove helpful.

One health claim that has garnered attention is green tea’s possible ability to prevent cancer. While some studies have yielded positive results, others have been contradictory, leaving cancer patients and survivors wondering what to pick at tea time. 

Jian-Min Yuan, MD, PhD, associate professor at the Masonic Cancer Center at the University of Minnesota in Minneapolis, says green tea’s anticancer activity is likely related to high levels of polyphenols, substances in plants that have antioxidant properties, such as protecting or preventing cells from free radical damage.

“Tea polyphenols, specifically tea catechins, are believed to be the active compounds in green tea that exert biological effects on cancer cells,” says Yuan. In laboratory studies, tea catechins’ antioxidant behavior reduced both the size and incidence of tumors and inhibited the growth of cancer cells. 

One catechin subgroup in green tea that has been studied is epigallocatechin-3-gallate (EGCG), which has been shown in laboratory studies to inhibit the growth of cancer cells, among other activities. Green tea has a high EGCG content.

Human studies, however, have been more elusive. “Human studies, observational epidemiological studies, suggest that green tea may have beneficial effects and warrant careful further investigation,” says Anna Wu, PhD, professor of preventive medicine at the University of Southern California. “However, it is difficult to conduct these epidemiological studies. In green tea-consuming populations—for example Japan—practically everyone drinks some green tea, and thus, you lack a clean, baseline group of non-green tea drinkers for comparison purposes.”

While some studies have yielded positive results, others have been contradictory, leaving cancer patients and survivors wondering what to pick at tea time. 

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