Abstract
Several studies have investigated the associations between diet and endometrial cancer, but few have focused specifically on coffee and tea. In a hospital‐based case–control study, we examined the associations between endometrial cancer risk and usual consumption of coffee, decaffeinated coffee, and black tea among 541 women with endometrial cancer and 541 women with an intact uterus but without a cancer diagnosis seen at Roswell Park Cancer Institute (Buffalo, New York) between 1982 and 1998. Daily frequency of consumption of coffee, decaffeinated coffee, and black tea in the few years prior to diagnosis in cases and questionnaire completion in controls was assessed with a self‐administered epidemiologic questionnaire and categorized as none, 0.5 cups/d, 1–2 cups/d and >2 cups/d. Odds ratios (OR) and 95% confidence intervals (CI) for each category referent to nondrinkers were estimated with unconditional logistic regression adjusting for age, endometrial cancer risk factors and each beverage mutually adjusted for other beverages. Compared to nondrinkers, we observed a nonsignificant negative association with endometrial cancer risk among women who reported >2 cups/d regular coffee (OR 0.71, 95% CI 0.49–1.03), a significant inverse association with >2 cups/d black tea (OR 0.56, 95% CI 0.35–0.90) and a significant inverse association with >4 cups/d combined coffee and tea consumption (OR 0.47, 95% CI 0.28–0.80). These findings suggest coffee and tea may be important in reducing endometrial cancer risk. © 2008 Wiley‐Liss, Inc.