Natural Factors Soy Isoflavone Complex capsules contain naturally balanced isoflavones including two major isoflavones,: genistein and daidzein. These two well known flavonoids are complemented by other healthful natural compounds found in soybeans and soy foods. The phytoestrogens in soy are known to help maintain a healthy menstrual cycle and mitigate menopausal symptoms without side effects. Although especially popular with women, soy isoflavones have also been shown to have benefits for men too. Epidemiological data show that prostate cancer is low in countries with high soy consumption. Soy isoflavones may be helpful for preventing certain cancers, osteoporosis and cardiovascular disease.