Estrone

What it isE1 — the weaker circulating estrogen, interconvertible with estradiol and the dominant estrogen after menopause.

Why it mattersPostmenopausal estrogen comes largely from aromatization of adrenal androgens in fat, arriving as estrone.

What it changesIts adipose-derived production is one mechanistic link between obesity and postmenopausal estrogen-sensitive cancers.