Boron supplementation may increase testosterone levels and decrease estrogen in males, though results are mixed.

“there are a couple of small trials like this one on testosterone and sex hormone binding globulin levels in males both of the studies did show an increase in testosterone with one of the studies showing a very significant increase in testosterone and a decrease in estrogen the other studies showing a more modest increase in testosterone and actually an increase in estrogen so I think it's unclear exactly what happens with regard to hormones and Boron but based on these studies it does look like Boron affects hormones in the human body”