Isoflavones comprise a class of organic compounds, often naturally occurring, related to the flavonoids. Many act as phytoestrogens in mammals. Being polyphenols, they're antioxidants. Some isoflavones and isoflavone-rich foods possess activity against cancer, including certain types of breast and prostate cancer. Isoflavones are produced almost exclusively by the members of the Fabaceae/Leguminosae (bean) family. Organic chemistry and biosynthesis Isoflavones of nutritional interest are substit… (More on Isoflavones)