The Common mushroom

is the world's most popular edible mushroom,

and is known by a large number of other names. Research at the City of Hope National Medical Center is studying whether this mushroom may inhibit breast cancer development. The reason mushrooms may reduce the risk of breast cancer, is because immunoassays have shown the mushroom can inhibit the enzyme aromatase which is used by the body to create estrogen.

In 2009, a case control study examined the diets of 2018 women, half of whom had been diagnosed with breast cancer. It found a statistically significant decrease of incidence of the disease in those women whose diets included more than 10 grams of fresh mushrooms per day (or the dry equivalent). Women in the study who consumed fresh mushrooms daily, were less likely to develop breast cancer, while those that combined a mushroom diet with regular green tea consumption, reduced their risk of breast cancer by nearly 90%. A similar case control study with 362 Korean women, found another strong association between mushroom consumption and decreased risk of breast cancer.

In vivo research has shown the table mushroom may be able to stimulate the immune system. In one study, the mushroom was found to enhance dendritic cell function. In vitro testing has shown a compound present in the table mushroom has anti-cancer properties, inhibiting the growth of HT29 colon cancer cells, Caco-2 colon cancer cells, MCF-7 breast cancer cells, and Rama-27 rat mammary fibroblasts. Agaricus bisporus, is a rare vegetable source of conjugated linoleic acid, and naturally possess antioxidants, like ergothioneine.