Green Tea & Cancer - Read what noted Oncologist Dr. Mitchell Gaynor's has to say about green tea. Select from our updated articles database for specific cancers:
Tea Reduces Ovarian Cancer Risk
People who drink a lot of tea or drink coffee in moderation are less likely to die of heart disease than coffee and tea abstainers, new research suggests. The finding adds to the growing body of evidence suggesting that coffee and tea help protect against heart disease, but not stroke. Researchers followed more than 37,000 people in The Netherlands for 13 years in one of the largest and longest studies ever to examine the impact of coffee and tea drinking on heart health. They found that: * People who drank three to six cups of tea per day had a 45% lower risk of death from heart disease than people who drank less than one cup of tea a day. * Drinking more than six cups of tea a day was associated with a 36% lower risk of heart disease, compared to drinking less than one cup. * People who drank more than two, but no more than four, cups of coffee a day had about a 20% lower risk of heart disease than people who drank more or less coffee or no coffee at all. * Moderate coffee consumption was associated with a slight, but not statistically significant, reduction in death from heart disease, but neither coffee nor tea affected stroke risk. The association was seen even though the researchers considered other lifestyle factors associated with heart disease, including smoking and exercise level. Submitted by Deborah Mitchell
Green Tea Prevents Ovarian Cancer
According to a report released this week, green tea extract shows promise for the treatment of uterine fibroids. The report summarized research done at the Center for Women's Health Research in the Department of Obstetrics and Gynecology of Meharry Medical College in Nashville. The January 2009 issue of the American Journal of Obstetrics & Gynecology published the findings. The team of researchers tested the effect of epigallocatechin gallate (EGCG) on fibroid tumors (leiomyoma) in rat cells and in nude mice, in vitro and in vivo, respectively. Diseased cells were introduced into the cells and mice, which were then fed doses of EGCG in the form of green tea extract in their drinking water. An inhibitory effect in the growth of the diseased cells was noted after 24 hours of treatment. According to an abstract of the report, the EGCG treatment "dramatically reduced the volume and weight of tumors at 4 and 8 weeks after the treatment." The team concluded that "EGCG effectively inhibits proliferation and induces apoptosis in rat ELT3 uterine leiomyoma cells in vitro and in vivo." The researchers, who have focused on finding treatments for uterine fibroids, were encouraged by the results. A statement released this week noted that 40 percent of reproductive age women suffer from the disease, which can be extremely painful, even debilitating. "If we can prove this compound is effective, millions of women can start self treatment and self management," Dr. Ayman Al-Hendy, who led the study, said in the statement.
Ovarian Cancer: General
In a clinical study conducted on ovarian cancer patients in China, researchers found that women who drank at least one cup of green tea per day survived longer with the disease than those who didn’t drink green tea. In fact, those who drank the most tea, lived the longest. Other studies found no beneficial effects.
Green Tea & Ovarian Cancer - Karolinska Study
Recent results in Dec 2005 from a study conducted at the Karolinska Institute in Stockholm, Sweden, show a relationship between the amounts of tea a middle-age woman drinks and her risk for ovarian cancer. The study, was published in the Dec. 12 issue of Archives of Internal Medicine. The researchers studied medical records of more than 61,000 women ages 40 to 76 who were part of a cancer survey. The women were also asked about their diets between 1987 and 1990. Fifteen years later, far fewer tea drinkers had been diagnosed with ovarian cancer. "We observed a 46 percent lower risk of ovarian cancer in women who drank two or more cups of tea per day compared with nondrinkers," the researchers reported. Also, women who drank one cup of tea per day had a 24-percent decrease in the incidence of ovarian cancer. The researchers contend a link between tea drinking and decreased ovarian cancer incidence is present as each additional cup of tea per day was associated with an 18 percent lower risk of ovarian cancer. The chemical specifically linked to protection from ovarian cancer has not been determined. Green tea has also shown promise in other areas. For one, it enhances the effectiveness of chemotherapy in ovarian cancer.
Green Tea & Ovarian Cancer - Shizuoka Study
study done at the University of Shizuoka, Japan, discovered that oral administration of green tea or theanine, an amino acid found in the leaves of green tea, synergized with the chemotherapy drug Adriamycin in lowering tumor weight. Adriamycin alone was ineffective. Theanine nearly tripled the concentration of adriamycin in the tumor tissue, while decreasing adriamycin levels in healthy tissue. In a more recent study, the same authors showed that theanine also synergizes with Adriamycin to inhibit liver metastases of ovarian cancer. This adds to the growing evidence that natural agents such as green tea can greatly enhance the effectiveness of conventional therapies.
Green Tea and Ovarian Cancer - China Study
In a study conducted on ovarian cancer patients in China, researchers found that women who drank at least one cup of green tea per day survived longer with the disease than those who didn’t drink green tea. In fact, those who drank the most tea, lived the longest.
References: Life Extension Magazine and other studies added.
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