[A case-control study on drinking green tea and decreasing risk of cancers in the alimentary canal among cigarette smokers and alcohol drinkers].
OBJECTIVE
To explore the role of green tea in decreasing the risks of gastric cancer, liver cancer, esophageal cancer among alcohol drinkers or cigarette smokers.


METHODS
A population based case-control study was conducted in Taixing, Jiangsu province.


RESULTS
In Taixing city, identified cases of stomach, liver and esophageal cancers were chosen with informed consent. The numbers were 206, 204, 218 respectively. Controls were chosen from normal population having lived in the area for longer than 10 years, also with informed consent. Green tea drinking seemed to have decreased 81%, 78%, 39% risk for the development of gastric cancer, liver cancer and esophageal cancer among alcohol drinkers. It might also have decreased 16%, 43%, 31% on the risks of developing the three kinds of cancers among cigarette smokers. Interaction assessment showed that drinking green tea could significantly decrease the risk of gastric cancer and liver cancer among alcohol drinkers, with ORs of interaction item 0.23 (95% CI: 0.10 - 0.55) and 0.25 (95% CI: 0.11 - 0.57) respectively.


CONCLUSIONS
Habit of drinking green tea seemed to have significant protective effects on the development of both gastric and liver cancer among alcohol drinkers while, green tea also having some protective effect on esophageal cancer among alcohol drinkers and on three kinds of cancers among cigarette smokers.
Mu
Li-na
LN
School of Public Health, Fudan University, Shanghai 200032, China.
Zhou
Xue-fu
XF
Ding
Bao-guo
BG
Wang
Ru-hong
RH
Zhang
Zuo-feng
ZF
Chen
Chuan-wei
CW
Wei
Guo-rong
GR
Zhou
Xiao-ming
XM
Jiang
Qing-wu
QW
Yu
Shun-zhang
SZ
D000328:Adult; D000368:Aged; D000428:Alcohol Drinking / Q000009:adverse effects*; D016022:Case-Control Studies; D002681:China / Q000453:epidemiology; D004067:Digestive System Neoplasms / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D004938:Esophageal Neoplasms / Q000209:etiology; D005260:Female; D005419:Flavonoids / Q000008:administration & dosage; D006801:Humans; D008113:Liver Neoplasms / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D010636:Phenols / Q000008:administration & dosage; D059808:Polyphenols; D012306:Risk; D012907:Smoking / Q000009:adverse effects*; D013274:Stomach Neoplasms / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control; D013662:Tea / Q000737:chemistry
D005419:Flavonoids; D010636:Phenols; D059808:Polyphenols; D013662:Tea