Naturally occurring non-binary HRT

Selective Estrogen Receptor Modulators
There is some evidence to suggest that certain phytoestrogens may act in a way analoguous to Selective Estrogen Receptor Modulators (SERMs). These phytoestrogens are reported to have a high affinity and agonism at ERβ, but the weak affinity and agonism at ERα. The point being that ERβ has a negative effect of mammary cell proliferation thus it may be plausible to use such phytoestrogens in conjunction with feminizing HRT or if AFAB to minimize breast growth while increasing other feminine features.

Isoflavones in particular are able to displace 17β-Estradiol at ER, among them the isoflavone genistein is known to directly agonize ERβ. This class of phytoestrogens are found predominantly in soy products.


 * Glycine max (Soy bean)

Potential Risks
Extended treatment with some non-synthetic sources of hormone replacement therapy is highly experimental and very little is known about it's long term effects. In the case of phyto- or xeno- hormones some are so obscure that it could be difficult to test for their blood concentration levels and thus proper regulation of dosage is impaired. In addition, dosage regulation is further impaired unless a proper extraction of the active constituent(s) is made, as the amount of substance in a given organism can vary batch to batch.