A scientific research study on eight healthy male volunteers showed that subjects supplementing with 10 mg of boron significantly increased free (active) testosterone levels and
decreased estrogenic activity as measured by a significant decrease in estradiol after only seven days.
Edit 2017: Recently, after learning about new research and working with even more women, I'm finding that plant - based phytoestrogens may promote ER beta
activity, which can lower
estrogenic potency in the body as a whole, thereby
decreasing the risk for certain cancers (this is not true of synthetic estrogen, like that in hormonal birth control or estrogen replacement therapy).