From University of California - Los Angeles
UCLA-led study first to show green tea helps prevent chronic gastritis
Green-tea drinkers suffer chronic gastritis half as often as nondrinkers, according to a new study led by researchers at the UCLA School of Public Health and Jonsson Comprehensive Cancer Center at UCLA. The findings are the first to link green tea to lower rates of chronic gastritis.
The study, published in the May edition of the peer-reviewed International Journal of Cancer, also supported previous research showing green-tea drinkers have lower risk of stomach cancer - in this case, 48 percent - than nondrinkers. In addition, researchers found as frequency and duration of tea drinking increased, the risk of both chronic gastritis and stomach cancer decreased.
Chronic gastritis is a common inflammatory disease that causes precancerous lesions of the stomach. The progression from chronic gastritis to stomach cancer is slow. Green tea contains antioxidants that researchers believe may inhibit the development of chronic gastritis and halt the progression of stomach cancer.
"This is the first time that green tea drinking was found to protect against chronic gastritis," said principal investigator and lead author Dr. Zuo-Feng Zhang, a professor of epidemiology in the UCLA School of Public Health. "The study suggests that using green tea to treat chronic gastritis and as a preventive therapy in high-risk populations would reduce the incidence of stomach cancer in the long term."
Researchers conducted the study in Yangzhong, China, investigating 133 stomach cancer cases, 166 chronic gastritis cases and 433 healthy individuals. Results were adjusted to account for differences in age, gender, education, body mass, cigarette smoking and alcohol consumption.
Incidence of stomach cancer is second only to lung cancer worldwide. Thirty-eight percent of stomach cancer cases in the world occur in China, where it remains the most common cancer in both sexes.
Tea, the most widely consumed beverage in the world, is derived from a single plant (camellia sinensis) and grown in 30 countries. Seventy-eight percent of the total produced for consumption is black, 20 percent green and 2 percent oolong. Green tea is consumed primarily in Asian countries, such as Japan and China, and in some parts of North Africa and the Middle East.
Primary funding for the study was provided with a grant from the NIH National Cancer Institute, Department of Health and Human Services.
In addition to Zhang, other researchers involved in the study were Veronica Wendy Setiawan and Qing-Yi Lu of UCLA; Guo-Pei Yu of New York Eye and Ear Infirmary; Yong-Liang Li of Columbia University; Ming-Lan Lu and Robert C. Kurtz of Memorial Sloan-Kettering Cancer Center; Ming-Rong Wang and Chun Hua Guo of the Yangzhon County (Peoples Republic of China) Anti-Epidemic Station; Shun-Zhang Yu of Shanghai Medical University; and Chung-Cheng Hsieh of the University of Massachusetts Cancer Center.
· UCLA School of Public Health: http://www.ph.ucla.edu/
· UCLA's Jonsson Comprehensive Cancer Center: http://www.cancer.mednet.ucla.edu/