A case-control study of stomach cancer in relation to Camellia sinensis in China

The purpose of our study was to investigate the association between green tea (Camellia sinensis) drinking habits and risk of stomach cancer in China.

A 1:2 matched hospital-based case-control study including 160 cases and 320 controls was conducted. A self-designed questionnaire was used to collect information on possible risk factors of stomach cancer, and to assess the green tea drinking habit. Conditional logistic regression was used to calculate odds ratios (ORs) and corresponding 95% confidence intervals (CIs).

Our study proposed that green tea was associated with risk of stomach cancer. Regular drinking (OR = 0.72), larger amount of consumption (≥35 g/week) (OR = 0.53) were protective factors. Among regular tea drinkers, lower temperature and longer interval between tea being poured and drunk also reduced the risk. Moreover, a strong agreement was found between temperature at which tea was drunk and tea interval (Correlation coefficient p value = 0.73).

Habits of green tea drinking, including regular drinking, larger amount of consumption, lower temperature and longer interval were strongly associated with a lower risk of stomach cancer.