Because the ultimate goal of a steroid cycle is to increase strength and muscle size, the associated spike in estrogen which accompanies steroids such as Testosterone is considered undesirable. In order to disassociate the two effects, two classes of drug are used. Medications such as Nolvadex or Clomid target the estrogen receptors. They make it more difficult for the estrogen to exert it’s influence within the body thus allowing the testosterone to act more freely. The second class is aromatase inhibitors such as Femara. They target the aromatase enzyme itself in order to prevent the production of estrogen in the first place. Sometimes, it’s not always clear which option you should go with or even what the differences are between the two. Lets clear that up a little.
Research suggests the common table mushroom has anti- aromatase  properties and therefore possible anti-estrogen activity. In 2009, a case-control study of the eating habits of 2,018 women in southeast China revealed that women who consumed greater than 10 grams of fresh mushrooms or greater than 4 grams of dried mushrooms per day had an approximately 50% lower incidence of breast cancer. Chinese women who consumed mushrooms and green tea had a 90% lower incidence of breast cancer.  However the study was relatively small (2,018 patients participating) and limited to Chinese women of southeast China.
In normal tissue, DIM (300nM) can activate the ATM genetic repair pathway in response to irradiation damage in a manner dependent on BRCA1 (one of its targets  ) without increasing survival of breast cancer cells (MDA-MB-231  ); there are known alterations in this pathway in some breast cancers where BRCA1 is reduced while ATM itself seems to be hyperactive, and oral supplementation of 300mg DIM has been noted to increase BRCA1 mRNA levels after 4-6 weeks supplementation (measured in white blood cells) in women who had a low activity mutation.