You have heavy periods. PMS that takes over a week of your life. Breast tenderness that gets worse in the days before your cycle starts. Headaches you can predict to the day. Mood that drops noticeably in the second half of your cycle. Maybe stubborn fat around your hips and thighs that does not budge regardless of what you do.
You have googled what is going on. The phrase that comes up most often is oestrogen dominance. The standard advice that follows is "just lower your oestrogen." Cut soy. Cut alcohol. Add a supplement. Maybe a juice cleanse.
Here is what you actually need to know before you do any of that. Oestrogen dominance is not always about high oestrogen. And "just lower it" misses how the picture usually develops in the first place. If you get the drivers right, the symptoms have somewhere to go.
What oestrogen dominance actually means
The phrase is often used to describe high oestrogen levels. That is not always what is happening.
More often, what we are looking at is oestrogen sitting high relative to progesterone. The ratio between the two is off, even when oestrogen itself sits inside a perfectly normal range on a blood test. The balance matters as much as the absolute number, and the balance is what produces most of the symptoms women come in with.
How the balance tips: three drivers
Three things usually play a part. Sometimes one of them is doing most of the work. More often, it is two or all three combining.
Driver one. Too much coming in.
The world we live in adds to your oestrogen load in ways our mothers did not have to think about. Compounds called xenoestrogens are chemicals that mimic oestrogen in the body. They are found in many plastics (particularly heated or aged plastics), in some cosmetics and personal care products, in pesticide residues on conventionally grown produce, in some receipt paper, and in many household cleaning products. Individually each exposure is small. Together, day after day, they add to the overall oestrogen signal your body is processing.
Driver two. Not enough progesterone.
Progesterone is the second-half-of-the-cycle hormone. It rises after ovulation. It calms the nervous system, supports deep sleep, buffers PMS symptoms, and crucially, it counterbalances oestrogen. When progesterone is low, oestrogen looks dominant by comparison even if its own levels are normal.
Three common reasons progesterone drops:
- Chronic stress, which redirects the building blocks your body needs for progesterone toward cortisol production instead
- Cycles without ovulation, which can happen with PCOS, in perimenopause, or simply in periods of high physical or emotional load
- Perimenopause itself, where progesterone is usually the first hormone to decline, often from the late 30s onwards
Driver three. Poor clearance.
Oestrogen is meant to circulate, do its job, and then be removed. The removal process happens primarily through the liver and then through the gut. If either system is sluggish, oestrogen can recirculate.
In the liver, oestrogen is processed through specific enzyme pathways that require particular nutrients to work properly. B vitamins, magnesium, sulfur-containing amino acids, and antioxidants are all needed. Low nutrient status slows the process.
In the gut, oestrogen that has been processed by the liver is meant to be carried out via the stool. If you are constipated, or if the bacterial balance in your gut is off (a population sometimes called the oestrobolome), the body can reactivate and reabsorb oestrogen that should have been on its way out, sending it back into circulation.
How it shows up
- Heavier or more painful periods
- Strong PMS, irritability, or mood swings before your period
- Breast tenderness and swelling
- Bloating in the second half of your cycle
- Headaches before your period
- Stubborn fat around the hips and thighs
- Feeling worse, not better, after ovulation
The honest bit: symptoms overlap
Here is the catch. The symptoms above can also come from thyroid dysfunction, PCOS, perimenopause, low oestrogen (which produces many of the same symptoms as high oestrogen), or simple iron deficiency. This is one of the trickiest spots in women's health. Patterns vary. A cluster of symptoms is a starting point, not a diagnosis.
This is why I test rather than assume. Symptoms get us started. Targeted testing narrows it down. A clear pattern lets us build a plan that targets the actual mechanism rather than the label.
Where I focus support
When the picture is genuinely one of oestrogen dominance, the work splits across three areas that mirror the three drivers.
Lower the incoming load
This is not about being perfect. It is about reducing the daily background exposure. Practical starting points:
- Store food and drink in glass or stainless steel rather than plastic, especially anything warm or acidic
- Choose simpler cosmetics and personal care products, avoiding parabens, phthalates, and "fragrance" listed as a single mystery ingredient
- Keep alcohol low. The liver processes alcohol before anything else, which means oestrogen waits its turn behind every drink
Support clearance
This is where food does the most work. The goal is to support both the liver pathways and the gut clearance route. Steady bowel movements, daily, are non-negotiable. So is a diet that actively feeds the liver enzymes and the gut bacteria that handle oestrogen processing.
Support the ratio
If low progesterone is part of the picture, the work shifts upstream. Supporting ovulation matters. That requires steady blood sugar, adequate calories, a manageable stress load, and the specific nutrients that support the luteal phase, particularly magnesium, vitamin B6, vitamin C, and zinc.
The foods that do the work, and why
The food side of this work is grounded in real research, not folk wisdom.
Cruciferous vegetables
Broccoli, cabbage, cauliflower, kale, Brussels sprouts, rocket. These contain compounds called glucosinolates which break down into indole-3-carbinol (I3C) and then, in the stomach, into DIM (diindolylmethane). Both compounds shift oestrogen metabolism in the liver, encouraging the production of the gentler 2-hydroxy oestrogen metabolites rather than the more proliferative 16-hydroxy ones.
This is not theoretical. A prospective clinical trial published in Carcinogenesis (Yerushalmi et al., 2020) studied DIM (3,3'-diindolylmethane) supplementation in healthy BRCA carriers and confirmed that DIM shifts oestrogen metabolism toward the gentler 2-hydroxy pathway. Whole cruciferous vegetables several times a week, in any form you enjoy them, do similar work over time.
Dietary fibre
Fibre does two related things. It binds oestrogen in the gut so it can be removed via the stool rather than reabsorbed. And it feeds the gut bacteria that keep your oestrobolome behaving. Recent research published in Cancer Causes & Control (Yaghjyan et al., 2023) directly linked the composition of the gut microbiome to endogenous oestrogen levels in healthy women, confirming what clinicians have observed for years: a gut that is well-fed and moving well clears oestrogen more efficiently.
The average woman eats less than half the fibre she needs. Most sit around 12 to 15g per day. The target for hormonal health is closer to 30g, ideally from a wide range of vegetables, legumes, fruits, nuts, seeds, and whole grains.
Ground flaxseed
Flax contains lignans, plant compounds that support healthier oestrogen metabolism and provide fibre at the same time. One to two tablespoons of ground flaxseed daily, added to yoghurt, porridge, or smoothies. It has to be ground, not whole, for the body to access the compounds.
Adequate protein
This one is often overlooked. Protein provides the amino acids the liver needs to run its clearance pathways properly. Methionine, cysteine, and glycine are particularly important for oestrogen processing. Inadequate protein, common in women who have been undereating for years, slows the entire clearance process.
Less alcohol
Alcohol competes with oestrogen for liver processing. Every drink pushes oestrogen further down the queue. Reducing alcohol is one of the highest-impact moves for oestrogen clearance, especially in women who drink several units across the week.
If this resonates
Oestrogen dominance is workable once you know which part of the picture is driving it. The fix is rarely about cutting everything out. It is about understanding where the disruption is happening in your body and supporting that specific system. The drivers respond to specific interventions. The symptoms ease as the mechanism improves.
This is exactly what I help women untangle in practice. We map the pattern, run any testing that makes sense, and build a response that fits your actual driver rather than the label.