[A case-control study on tea consumption and the risk of lung cancer]

To investigate the association between tea consumption and lung cancer.

A case-control study was conducted, including 1225 newly diagnosed cases with lung cancer and 1234 healthy control subjects frequently matched by gender and age (+/- 3 year). Epidemiological data were collected by in-person interviews using a standard questionnaire. The adjusted odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated by fitting multivariate unconditional logistic regression models that included potential confounding factors.

A protective effect of tea drinking on risk of lung cancer was observed for non-smokers with adjusted OR was 0.465 (95% 0.345 - 0.625), and the risks decreased with increased years of tea drinking. The adjusted ORs for drinking green tea, black tea, oolong tea and others was 0.333 (95% CI 0.154 -0.720), 0.522 (95% CI 0.356 - 0.767), 0.735 (95% CI 0.424 - 1.274) and 0.267 (95% CI 0.143 - 0.497), respectively. The inverse associations were also observed between frequency, concentration, consumption and risk of lung cancer among non-smokers. Tea drinking was associated with decreased risk of lung cancer for those smokers with drinking tea < 3 times/week and low concentration, with the adjusted ORs of 0.453 (95% CI 0.286 - 0.717) and 0.518 (95% CI 0.346 - 0.778), respectively.

The protective effect of tea drinking was observed on the risk of lung cancer, especially for non-smokers.