Isoflavone phytoestrogen — binds ER-β preferentially (10–20× over ER-α). Gut microbial conversion by Slackia isoflavoniconvertens / Adlercreutzia equolifaciens yields S-equol, the more active metabolite — only ~25–50% of adults are 'equol producers' depending on gut composition, which explains much of the clinical heterogeneity in soy studies.
Half-Life (t½)
PO: 7.8h
Dosing Guidelines
PO: Typical 53.3 mg (Range: 40–80 mg)
Target Organ Systems
digestive
Interactions
Genistein (synergistic): Co-occur in soy isoflavone fractions; combined ER-β activity is the usual clinical exposure.