Genistein
Most abundant and biologically active soy isoflavone — phytoestrogen with binding affinity for oestrogen receptors ERα and ERβ. Inhibits tyrosine kinases and topoisomerase II. Studied for cancer prevention, bone health, menopausal symptoms, and cardiovascular risk. More potent oestrogenic activity than daidzein.
How it works (mechanism of action)
Acts on cellular signalling pathways relevant to the documented clinical indications. Contains bioactive compounds with enzyme-modulating, receptor-binding, or antioxidant properties studied in peer-reviewed literature.
HORMONE-SENSITIVE CANCERS: Contraindicated in ER+ breast cancer — conflicting data; some studies show proliferative effects in some ER+ cell lines. Endometrial cancer, uterine fibroids, endometriosis: AVOID. Thyroid: inhibits thyroid peroxidase — avoid in hypothyroidism or take separately from thyroid medication. Drug interactions: tamoxifen. Male: may reduce testosterone at high doses. Pregnancy: phytooestrogenic effects.