Tea May Protect against Digestive Cancers
Middle age and older women who drink three or more cups of tea each week have lower risk of colon, esophagus and other digestive system cancers, suggests a large new study conducted among Chinese women. The study adds to the evidence on tea and cancer, an area where current research has drawn conflicting findings.
Published in the American Journal of Clinical Nutrition, the study analyzed data from almost 70,000 women who were part of the Shanghai Women’s Health Study. Study researchers gathered data on tea drinking and other lifestyle habits when the women entered the study, at ages 40 to 70, and every two to three years thereafter.
Over a quarter of the women – 28 percent – were regular tea drinkers. Study researchers defined this as drinking at least three cups of tea a week for at least six months.
After 11 years, researchers found that regular tea drinkers had a 14 percent reduced risk of all digestive system cancers combined, compared to non-tea drinkers. Drinking two to three cups daily – as opposed to three cups weekly – reduced their risk even more: 21 percent. This is after the researchers took into account their diet, exercise, family history of cancer and other risk factors. They did not find any link between tea and the individual cancers, which included stomach, esophagus, colorectal, liver, pancreas and gallbladder/bile duct.
When the scientists looked at the effects of tea drinking for 20 or more years, the protective effect appeared even slightly stronger for all digestive system cancers combined and colorectal cancers. As the authors note, that supports the potential importance of long-term, cumulative effect of tea in reducing the risk of colorectal cancer, which can develop over decades
Source: Nechuta, S. et al. “Prospective cohort study of tea consumption and risk of digestive system cancers: results from the Shanghai Women's Health Study.” Am J Clin, Nutr November 2012 vol. 96 no. 5 1056-106.