Dietary Flavonoid Intake, Black Tea Consumption, and Risk of Overall and Advanced Stage Prostate Cancer
Menée sur une cohorte néerlandaise incluant 58 279 hommes, cette étude évalue l'association entre la consommation de flavonoïdes d'origine alimentaire (catéchine, épicatéchine, kaempférol et myricétine) ou de thé noir et le risque de développer un cancer de la prostate (3 362 cas dont 1 164 cas de stade avancé sur la période 1986-2003)
Flavonoids are natural antioxidants found in various foods, and a major source is black tea. Some experimental evidence indicates that flavonoids could prevent prostate cancer. We investigated the associations between flavonoid intake, black tea consumption, and prostate cancer risk in the Netherlands Cohort study, which includes 58,279 men who provided detailed baseline information on several cancer risk factors. From 1986 to 2003, 3,362 prostate cancers were identified, including 1,164 advanced (stage III/IV) cancers. Cox proportional hazards regression using the case-cohort approach was used to estimate hazard ratios and 95% confidence intervals. Intake of total catechin, epicatechin, kaempferol, and myricetin and consumption of black tea were associated with a decreased risk of stage III/IV or stage IV prostate cancer. Hazard ratios of stage III/IV and stage IV prostate cancer for the highest versus the lowest category of black tea consumption (≥5 versus ≤1 cups/day) were 0.75 (95% confidence interval: 0.59, 0.97) and 0.67 (95% confidence interval: 0.50, 0.91), respectively. No associations were observed for overall and nonadvanced prostate cancer. In conclusion, dietary flavonoid intake and black tea consumption were associated with a decreased risk of advanced stage prostate cancer.