Study Finds Drinking Tea May Help Protect Against Liver Cancer, Especially in Women
By Greg Arnold, DC, CSCS, July 10, 2006, abstracted from “Tea drinking and the risk of biliary tract cancers and biliary stones: A population-based case-control study in Shanghai, China” in the June 15, 2006 issue of the International Journal of Cancer
The biliary tract is a network of vessels that connects the liver, gallbladder and pancreas, and is responsible for transporting bile, a fluid made in the liver, to the intestines to help digest food.1 Aproximately 7,500 new cases of biliary tract cancer (which include gallbladder and bile duct cancer) are diagnosed per year.2 Patients are advised to seek medical attention if they start to have jaundice (yellowing of the skin), clay-colored stools, and cola-colored urine.3
Because current medical treatments that include surgery, chemotherapy, and radiation can produce at best a five-year survival rate,4 prevention of biliary cancer is a priority. Now a new study5 has found that drinking tea may help protect against biliary cancer, especially in women.
In the study, researchers studied 627 residents of urban Shanghai between 35 and 74 years of age who were newly diagnosed with biliary tract cancer between June 1997 and May 2001. They also selected over 1,000 patients with biliary stones without a history of cancer and 959 subjects with no history of any type of cancer (or biliary stones) as controls. Each patient was interviewed about their lifestyle behaviors and diet, especially tea drinking, including the age they started drinking tea, how many years they have been drinking tea, and their monthly intake (weight of tea leaves in grams).
The researchers found that among women, those who drank tea who consumed at least one cup of tea per day for more than six months had a 44% reduced risk of gallbladder cancer, a 35% reduced risk of bile duct cancer, and a 27% reduced risk of biliary stones. In addition, their age of first use, duration, monthly intake and lifetime consumption were "significantly and inversely associated" with gallbladder cancer risk.
92% of tea drinkers reported green tea as their tea of choice. This statistical significance, however, was not found in men despite having longer durations and higher consumptions of tea than women.
For the researchers, this study revealed "a protective effect of tea consumption on biliary tract cancer and biliary stones among women." They attributed this protective effect to tea polyphenols, in particular EGCG, known to have a number of health-promoting properties.6
Greg Arnold is a Chiropractic Physician practicing in Danville, CA. You can contact Dr. Arnold directly by emailing him at mailto:ChiroDocPSUalum@msn.com or visiting his website www.CompleteChiropracticHealthcare.com
Reference:
1 “Bile Duct” posted on wikipedia.com http://en.wikipedia.org/wiki/Bile_duct
2 de Groen PC. Biliary Tract Cancers. NEJM 1999;341:1368-1378
3 Pitt HA, Dooley WC, Yeo CJ, Cameron JL. Malignancies of the biliary tree. Curr Probl Surg 1995;32:1-90
4 Henson DE, Albores-Saavedra J, Corle D. Carcinoma of the gallbladder: histologic types, stage of disease, grade, and survival rates. Cancer 1992;70:1493-1497
5 Zhang XH. Tea drinking and the risk of biliary tract cancers and biliary stones: A population-based case-control study in Shanghai, China. Int Jou Cancer 2006; 118(12): 3089-3094
6 Mukhtar H, Ahmad N. Tea polyphenols: prevention of cancer and optimizing health. Am J Clin Nutr 2000; 71: 1698S-1702S