ScienceDaily (Oct. 26, 2010) — Green tea does not protect against breast cancer. A study of data from approximately 54,000 women, published in BioMed Central's open access journal Breast Cancer Research, found no association between drinking green tea and breast cancer risk.
Motoki Iwasaki, from the National Cancer Center, Tokyo, worked with a team of researchers to carry out the study. He said, "Although in vitro and animal-based studies have suggested that green tea may have beneficial protective effects against breast cancer, results from human studies have been inconclusive. Our large-scale, population-based prospective cohort study is one of the first to include a wide range of tea intakes; women who drank green tea less than 1 cup per week to those who drank 10 or more cups per day. It found no overall association between green tea intake and the risk of breast cancer."