A prospective study of green tea consumption and oral cancer incidence in Japan

Ann Epidemiol. 2007 Oct;17(10):821-6. doi: 10.1016/j.annepidem.2007.04.003. Epub 2007 Jul 2.


Purpose: To examine the relation of green tea consumption with oral carcinogenesis, we prospectively analyzed data from a nationwide large-scale cohort study in Japan.

Methods: A total of 20,550 men and 29,671 women aged 40-79 years, without any history of oral and pharyngeal cancer at baseline survey, were included in the present study. During a mean follow-up period of 10.3 years, 37 oral cancer cases were identified. The Cox proportional hazard model was used to estimate the hazard ratio (HR) and 95% confidence interval (95% CI) for oral cancer according to green tea consumption by sex, while adjusting for age, smoking, alcohol drinking, and other dietary factors.

Results: For women, the HRs of oral cancer for green tea consumption of 1-2, 3-4, and 5 or more cups per day were 0.51 (95% CI: 0.10-2.68), 0.60 (95% CI: 0.17-2.10), and 0.31 (95% CI: 0.09-1.07), respectively, compared with those who drank less than one cup per day (p for trend, 0.08). For men, no such trends were observed.

Conclusions: Our findings did not suggest a prominent inverse association of green tea consumption with oral cancer, although there was a tendency for a reduced risk in women.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Cohort Studies
  • Female
  • Humans
  • Japan / epidemiology
  • Male
  • Middle Aged
  • Mouth Neoplasms / epidemiology*
  • Proportional Hazards Models
  • Prospective Studies
  • Risk Factors
  • Tea* / adverse effects


  • Tea