Tea intake and risk of colon cancer in African-Americans and whites: North Carolina colon cancer study.

Abstract

Tea polyphenols have been shown to exhibit anti-cancer activity, but the epidemiological findings are inconsistent. We examined the association between tea consumption and colon cancer in a population-based study in North Carolina. The analysis included 630 cases and 1040 controls frequency matched to cases by age, gender, and race. The odds ratios (OR) for tea consumption, adjusted for age and gender, were calculated for African-Americans and Whites and effect modification by race was explored. No association was found between tea consumption and colon cancer overall. Compared to non-consumers, those who consumed <2 servings/day or > or = 2 servings/day had OR = 0.9 (95% CI: 0.7-1.2) and OR = 1.3 (95% CI: 0.9-1.8) respectively. Other risk factors for colorectal cancer (family history of colorectal cancer, exposure to non-steroid anti-inflammatory drugs, meat cooking practices, smoking, physical activity, body mass index, intake of red meat, fruits, vegetables, and alcoholic beverages) did not influence these associations. We did not find any evidence of effect modification by race on either on the multiplicative or additive scale. We conclude that, contrary to expectation, tea drinking did not decrease the risk of colon cancer in this study population.