Tea consumption reduces ovarian cancer risk.

Objective: To ascertain the relationship between tea drinking and the risk of ovarian cancer among southern Chinese women, a case-control study was conducted in southern China during 2006-2008.

Methods: Five hundred incident patients with histologically confirmed epithelial carcinoma of the ovary and 500 controls (mean age 59 years) were recruited from four public hospitals in Guangzhou. Information on frequency, quantity and duration of tea drinking, amount of dried tea leaves brewed, together with habitual diet and lifestyle characteristics, was obtained face-to-face from participants using a validated and reliable questionnaire. Logistic regression analyses were performed to assess the association between tea consumption variables and the ovarian cancer risk.

Results: The control subjects reported higher tea consumption levels and prevalence (78.8%) than the ovarian cancer patients (51.4%). Regular drinking of green tea, black tea and/or oolong tea was associated with a lower risk of ovarian cancer, the adjusted odds ratio being 0.29 (95% confidence interval 0.22-0.39) after accounting for confounding factors. When compared with non-drinkers, apparent inverse dose-response relationships were observed for years of drinking, number of cups and quantity of tea consumed, as well as amount of dried tea leaves brewed (p < 0.01).

Conclusion: Regular tea consumption is associated with a reduced risk of ovarian cancer for southern Chinese women.