I keep reading in places that boldenone aromatizes to estrone, which I don’t think is true. Only androstenedione (and prohormone precursors) will aromatize to E1.
However, estrone is both a precursor to and metabolite of estradiol via 17β-HSD1/2. So maybe boldenone and perhaps some metabolites/derivatives (including DHB & primobolan) induce or inhibit these enzymes affecting E1/E2 balance?
This would be sort of a similar case to nandrolone, which barely aromatizes but either upregulates expression of aromatase and/or sensitizes the ER to trans activation by estrogen - that’s why adding it to a cycle so commonly results in gyno or ED despite producing nearly extra estrogen on its own.
@Type-IIx any thoughts on this?