Fibroids, Ovarian Cysts and Blood Sugar
Why insulin and estrogen keep appearing together in gynaecological conditions — and what diet can and can't offer.
"I have a fibroid and ovarian cyst and PCOS."
There's a plausible connection here, and I want to be careful not to oversell it.
The shared thread
Insulin and estrogen interact. High insulin lowers sex hormone binding globulin, which increases the amount of unbound, active hormone circulating — including estrogen.
Fibroids are estrogen-responsive: they tend to grow when estrogen is high and shrink after menopause when it falls. Ovarian cysts in PCOS are driven by the androgen and ovulation disruption that high insulin contributes to.
So insulin resistance appears in the background of several of these conditions rather than causing any of them directly.
What I can honestly claim
That improving insulin sensitivity is a reasonable thing to do if you have these conditions, and that it's likely to help the broader hormonal picture.
What I can't claim is that diet shrinks fibroids. The evidence for dietary treatment of fibroids specifically is thin. Fibroids are managed medically and surgically, and if yours are causing heavy bleeding, pain or pressure, that's a gynaecological conversation rather than a nutritional one.
I'd rather tell you that than let you spend six months on food while symptoms continue.
What's genuinely worth doing
Improve insulin sensitivity through the usual levers — protein-led meals, carbohydrate placed and paired, resistance training, sleep.
Address iron if bleeding is heavy. Fibroids commonly cause heavy periods, and iron deficiency is both common and frequently missed. Fatigue attributed to hormones is sometimes anemia. Worth asking for ferritin, not just hemoglobin.
Fiber matters here for a specific reason — it supports the elimination of estrogen metabolites through the gut. That's a real mechanism, though its practical magnitude is uncertain.
Alcohol is associated with higher estrogen levels, which is worth knowing if you're managing an estrogen-responsive condition.
Try this week: if your periods are heavy, ask your doctor to check ferritin. That's the most likely quick win in this cluster.
Education, not medical advice. Fibroids and cysts should be managed by a gynaecologist.