Consumption of Black Tea and Cancer Risk: a Prospective Cohort Study

Background: Tea is one of the most frequently consumed beverages in the world. Antioxidant polyphenol compounds (such as catechjns and flavonols) are abundantly present in both green and black teas and have been observed to have anticarcinogenic properties in cell and animal model studies. In black tea, however, most of the catechins have been oxidized to forms that may have reduced anticarcinogenic properties. Despite indications from experimental studies that tea may protect against cancer, epidemiologic evidence has been inconclusive. Purpose: The association between black tea consumption and the subsequent risk of stomach, colorectal, lung, and breast cancers was investigated in The Netherlands Cohort Study on Diet and Cancer among 58 279 men and 62 573 women aged 55-69 years. Methods: Sub-jects in the cohort completed a self-administered question-naire on dietary habits and other risk factors for cancer at base line in 1986. Follow-up for cancer was done by means of computerized record linkage with all nine regional cancer registries in The Netherlands and the national patholog