A new prospective study has reported that consumption of black tea, coffee, and caffeine are not associated with risk of breast cancer among African-American women. Previous prospective studies of tea and coffee intake and risk of breast cancer have produced inconsistent results. None of the prior studies reported separately on African-American women. The current study included 52,062 women aged 21 to 69 at enrollment in 1995 in the Black Women’s Health Study. Dietary intakes were determined in 1995 and in 2001. The women were followed for 12 years through 2007. A total of 1,268 new cases of breast cancer were diagnosed during the follow-up period.

The authors compared breast cancer rates between those consuming at least four cups of tea or caffeinated coffee per day and those consuming no tea or coffee. They also compared breast cancer rates between those with the highest and lowest fifths of total caffeine intake. Tea, coffee, and caffeine were not found to be associated with risk of breast cancer. In addition, tea, coffee, and caffeine consumption was not found to be linked to risk of breast cancer based on menopausal status or estrogen or progesterone receptor status. The authors conclude that the findings suggest that intakes of tea, coffee, and caffeine are not associated with risk of breast cancer among African-American women.

Comments concerning the study

The study results parallel those of many other studies of coffee and tea drinking and risk of breast cancer among European and Asian populations. However, interest in this topic has continued over quite some time among researchers, indicating that they expect some associations to be uncovered if only they focus on the "right" subgroups of women, types of breast cancer, or other factors. In fact, some associations have been found for those with benign fibrocystic breast disease, lobular breast cancer, BRCA1 or BRCA2 mutations, and other factors. Please see our articles on coffee, black tea and green tea.