The study was published in the March 15, 2009 issue of the International Journal of Cancer.
The paper (volume 124, issue 6, pages 1404-1408) entitled “Dietary intakes of mushrooms and green tea combine to reduce the risk of breast cancer in Chinese women,” shows the results by Australian researchers Min Zhang and C.D’Arcy J. Holman (The University of Western Australia), and Chinese researchers Jian Huang and Xing Xie (Zhejiang University School of Medicine).
The Australian-Chinese team studied 1,009 females between the ages of 20 and 87 years with “histologically confirmed breast cancer.”
The women were from southeastern China and the study was performed from 2004 to 2005.
A control group of healthy Chinese women (and without breast cancer)—numbering 1,009 and of similar ages—also participated in the study.
Women in China were studied because on average the incidence of breast cancer is one-fifth less in these women as it is in women in Western industrialized countries.
Data was collected on the frequency and quantity of dietary intake of mushrooms and consumption of green tea with questionnaires from face-to-face interviews.
The results of the study is found on page two.
The Chinese and Australian researchers found that the women who consumed the most quantities of fresh mushrooms were about two-thirds (36%) less likely to develop breast cancer, when compared to women who did not eat mushrooms.
With respect to dried mushrooms, the researchers found that eating four grams or more were sufficient to minimize the risk of breast cancer in the Chinese participants.
Specifically, the study found that the women who ate dried mushrooms were 53% less likely to get breast cancer then women who did not eat mushrooms.
They researchers also found a decrease in breast cancer risk from women who ate mushrooms and drank green tea, at least 1.05 grams of dried green tea leaves per day.
They state in the abstract to their paper, “We conclude that higher dietary intake of mushrooms decreased breast cancer risk in pre- and postmenopausal Chinese women and an additional decreased risk of breast cancer from joint effect of mushrooms and green tea was observed.”
They suggest that additional research is needed to examine in more details the links and mechanisms of dietary mushrooms and green tea and the incidences of breast cancer in women.