Fibroids are hormone-driven. Understanding which hormones matter — and why — gives you a clear framework for the lifestyle choices that actually move the needle.
Estrogen: The Primary Driver
Fibroids express estrogen receptors at significantly higher levels than normal uterine tissue. Estrogen drives fibroid cell proliferation and suppresses natural cell death. Fibroids follow estrogen’s curve: appearing in reproductive years, growing during pregnancy, regressing after menopause. Estrogen-lowering medications reliably shrink them, confirming the mechanism.
Key estrogen elevators: excess body fat (aromatase converts androgens to estrogen in fat cells), poor liver clearance, low fibre intake, alcohol, and xenoestrogens from plastics and pesticides.
Progesterone, Cortisol and IGF-1
Progesterone’s role is more complex than simple opposition to estrogen — fibroids also express progesterone receptors. Chronic stress raises cortisol, which suppresses progesterone, worsening estrogen dominance. Insulin-like growth factor 1 (IGF-1) — elevated in insulin resistance — directly stimulates fibroid cell growth, making blood sugar management via dietary choices directly relevant. For a deeper dive see our article on the role of hormones in fibroid development.
Related reading: How To Talk To Your Doctor About Fibroids: Getting The Conversation Right · Fibroids And Estrogen Dominance: Understanding The Connection · Fibroids And Frequent Urination: Why It Happens And What You Can Do
