Chinese women who regularly eat mushrooms and drink green tea daily have 89% less risk of developing breast cancer than those who consume neither.

Australian researchers from the University of Perth compared the diets and lifestyles of more than 2000 women who attended a breast clinic in China. Working with detailed registers of their consumption of a variety of foods, they observed that, all other factors being equal, women who consumed an average of more than 10 g of fresh mushrooms every day had 64% less risk of developing breast cancer than those who did not eat mushrooms. Those who ate 4 g of dried mushrooms saw their risk diminish by 47%. When consumption of green tea was added (more than 1g of tea-leaves infused per day), the protective effect of the two factors combined reached 89%! [1]
 
We already knew that Japanese farmers who have a large consumption of these mushrooms are up to half as likely to develop stomach cancer (which is frequently observed in Japan) as people who do not eat them. [2]. Several large cancer centers in Japan now systematically deliver standardized extracts of these mushrooms to accompany chemotherapy treatments [3, 4, 5]. Japanese researchers have observed that patients who receive these mushroom extracts see the number and activity of their white blood-cells increase sharply, including in the interior of the actual tumor [4, 6, 7, 8, 9]. At Kyushu university researchers have observed that when chemotherapy is accompanied or followed by consumption of these mushrooms in patients suffering from colon cancer, they considerably extend the patient’s survival [4].
 
In the Montreal lab headed by Prof Richard Béliveau, extracts of various mushrooms have been tested against breast cancer cells in vitro. The benefits are not limited to Asian mushrooms: some mushrooms in the pleurotus family enable the almost complete cessation of growth of cancer cells in the laboratory.
 
Although the effects of mushrooms on cancer were already partially known, what is surprising in this study is their potentialization through the consumption of green tea. The principle of the synergy of different food products is a constant feature when we explore the action of our natural defense system against cancer.
 
Bibliography

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9.    Mizutani, Y. and O. Yoshida, Activation by the protein-bound polysaccharide PSK (krestin) of cytotoxic lymphocytes that act on fresh autologous tumor cells and T24 human urinary bladder transitional carcinoma cell line in patients with urinary bladder cancer. Journal of Urology, 1991. 145(5): p. 1082-7.
10.    Béliveau, R. and D. Gingras, Cooking With Foods That Fight Cancer (McClelland Stewart, 2007).