Sipping Away Cancer Risks

Gastric cancer risks may be lower in green tea drinkers

(RxWiki News) Drinking green tea has been associated with everything from longer life to improving memory. It’s healthy stuff that may keep our DNA strong. Green tea may be adding a new anti-cancer benefit to its resumé.

Researchers have found that women who drink green tea regularly have lower risks of cancers that affect the digestive system. These include cancers of the esophagus, gallbladder, bile ducts, liver, pancreas, stomach and intestines.

Women who were regular green tea drinkers had a 17 percent lower risk of developing any type of digestive cancer.

"Consider adding green tea to your diet."

What’s so healthy about green tea? It contains catechins – natural chemicals – that have antioxidant properties. These chemicals are believed to help prevent DNA damage which can lead to the development and spread of cancer.

Researchers at Vanderbilt Ingram Cancer Center made the discovery. The lead investigator was Wei Zheng, MD, PhD, MPH, professor of Medicine and director of the Vanderbilt Epidemiology Center, and Sarah Nechuta, PhD, MPH, assistant professor of Medicine, was the study’s lead author.

Investigators interviewed women who were participating in the Shanghai Women’s Health Study – a study involving some 75,000 Chinese women who were middle-aged and older.

The women were asked if they drank tea and what kind they drank. Most of the Chinese women reported drinking mostly green tea. Researchers defined regular tea consumption as drinking green tea at least three times a week for six months or longer.

The more green tea that was consumed, the lower the cancer risks:

  • 2-3 cups daily equated to a 21 percent decrease GI cancer risk.
  • The greatest benefit was seen in lower risks of esophageal, stomach and colorectal cancers.

“For all digestive system cancers combined, the risk was reduced by 27 percent among women who had been drinking tea regularly for at least 20 years,” said Dr. Nechuta. “For colorectal cancer, risk was reduced by 29 percent among the long-term tea drinkers. These results suggest long-term cumulative exposure may be particularly important.”

The women were also asked about lifestyle issues, eating and exercise habits, education and occupation. None of the participants smoked or drank alcohol.

The tea drinkers tended to be better educated and younger. They also ate more fruits and vegetables and exercised more.

“Although we adjusted for these factors and other lifestyle factors, we cannot rule out residual confounding due to unmeasured or poorly measured factors,” the authors wrote.

Findings from this study were published November 1 in the American Journal of Clinical Nutrition. The National Cancer Institute funded this research. No conflicts of interest were reported.

Review Date: 
November 6, 2012