Boron's ability to induce sex hormone levels give it a role preventing chronic disease. For example, adequate dietary boron may potentially reduce risk of lung cancer (1). The effects also explain why boron supplementation may support bone density guarding against osteoporosis (2).
However, caution should be exercised before supplementation with boron. Greater estrogen levels due to boron supplementation may potentially increase risk of breast cancer (1;2). Thus, boron should not be taken by women with high risk of breast cancer or who've had breast cancer.