Compound Monograph
Genistein
A soy isoflavone and phytoestrogen that binds estrogen receptors and is one of the principal isoflavones of legumes.
Classification
Genistein is an isoflavone (phytoestrogen), part of the phenolics class. Antioxidant compounds built around one or more phenol rings — the flavonoids, tannins, phenolic acids, coumarins, and pigments behind much of a plant's protective chemistry.
Where Does It Come From? (5)
Genistein is a naturally occurring isoflavone (phytoestrogen), found in Soybean, Red clover, Broom and 2 other sources. It is well tolerated orally (low toxicity).
Research & Evidence
Genistein is one of the principal isoflavones of soybeans and other legumes such as red clover, and it gives its name to the broom genus Genista from which it was first isolated. It is a phytoestrogen: it binds estrogen receptors, with relative preference for ER-beta, and can produce weak estrogenic or anti-estrogenic effects depending on context. It also inhibits certain tyrosine kinases and topoisomerases in laboratory systems. Genistein has been extensively studied in relation to bone health, menopausal symptoms, hormone-sensitive tissues and metabolism, though human findings are mixed.
Toxicity & Safety
Genistein is consumed in significant amounts in soy-based diets and is generally well tolerated. Because it is hormonally active, there is ongoing discussion about its effects in hormone-sensitive conditions and in concentrated supplement form, and people with such conditions may wish to take dietary caution.