What is Oestrogen Dominance and Why Does it Matter?

The term ‘oestrogen dominance’ is thrown around a lot in the health world. But what does this term mean, and why is it important to care about? 

Oestrogen dominance is not just high levels of oestrogen. It is a hormonal imbalance where the levels of oestrogen in the body are high in relation to progesterone.

Are You Oestrogen Dominant? The Telltale Signs

When we assess people for oestrogen dominance, we look for a combination of symptoms, lifestyle cues and test results to flag this as a possibility or for further investigation. Some common symptoms of oestrogen dominance include:

  • Menstrual irregularities such as heavy, irregular or painful periods
  • Recent weight gain – most often disproportionately located around the hips, thighs and abdomen
  • Mood issues which may feel like anxiety, irritability, and depression
  • Breast changes – tenderness around your period or at ovulation, increase in size, or fibrocystic breasts
  • Fatigue
  • Decreased libido
  • Bloating or water retention
  • Headaches
  • Nausea – most often around ovulation but can also occur throughout the cycle

What’s Causing the Imbalance? Unveiling the Root Causes of Oestrogen Dominance

Many factors may play a role in the development of oestrogen dominance. Diagnosis of oestrogen dominance can generally be grouped into two categories:

  • Too much oestrogen.
    • External factors such as certain medications (for example the oral contraceptive pill) hormonal therapy, or environmental exposure. Exposure to compounds called xenoestrogens can mimic the effect of oestrogen in the body. Examples of xenoestrogens include BPA & phthalates found in plastic food containers, water bottles, personal care products, pesticides and household cleaning products.
    • Internal factors such as endocrine disorders resulting in overproduction of oestrogen, gut issues (such as bacterial overgrowth) or liver issues resulting in poor detoxification of oestrogen.
  • Not enough progesterone
    • Ageing – as we age, our levels of progesterone naturally drop which can result in a relative dominance of oestrogen, even with normal or low oestrogen levels.
    • Lack of ovulation. If ovulation does not occur, there is no corpus luteum formed, and therefore reduced levels of progesterone are produced. Lack of ovulation can occur for a variety of reasons including the contraceptive pill, over-exercising, nutrient deficiencies, chronic stress or pituitary disorders.

But, what causes these imbalances to occur in the first place?

  • Stress
    • Cortisol – when we are stressed, our body prioritises the production of cortisol (the ‘stress hormone’) over progesterone. This process is known as the ‘progesterone steal’.
    • Disruption of HPA/ HPO axis – Cortisol and the flow-on effects of chronic stress can disrupt the communication from our brain to our adrenal glands and ovaries, affecting the balance of reproductive hormones like oestrogen and progesterone.
  • Sleep – inadequate sleep can disrupt hormonal regulation, while also exacerbating symptoms of hormonal imbalances.
  • Increased liver burden, impaired detoxification or microbiome imbalances. To process oestrogen and keep levels in check, your liver must first detoxify excess levels. This requires key nutrients as well as a healthy, well-balanced microbiome. If there is an overgrowth of bacteria in the gut, aside from digestive symptoms, these bacteria can have the unwanted effect of reducing the body’s ability to detoxify oestrogen.
  • Endocrine disorders which can affect the balance of oestrogen and progesterone, such as:
    • Fibroids
    • Polycystic Ovarian Syndrome (PCOS)
    • Hypothyroidism
    • Insulin resistance
    • Endometriosis
    • Certain cancers such as breast, uterine, ovarian, and adrenal tumours
  • Dietary Factors
    • Nutrient deficiencies such as magnesium, vitamin B6, zinc, folate, omega 3’s, protein and fibre can impair the body’s ability to produce and regulate hormones.

Potential Health Consequences of Oestrogen Dominance

Effective treatment of oestrogen dominance does not have to be aggressive. There are so many strategies we can use to identify and correct the root cause – which may be different for each individual.

Left untreated, oestrogen dominance can increase the risk of developing certain cancers, osteoporosis, heart conditions, and reduced quality of life. It can also exacerbate symptoms of hormonal disorders such as endometriosis and PCOS.

Taking Back Control: Natural Strategies to Reduce Oestrogen Levels


  • Increase dietary phytoestrogens. Phytoestrogens occur in plant foods that help to block oestradiol from oestrogen receptors. Flaxseeds and soy products are great sources of phytoestrogens.
  • Fibre – aim for 30g daily. Getting adequate fibre is not only fantastic for your microbiome, but supports the clearance of oestrogen through the bowels.
  • Aim for a mostly whole foods diet. By reducing your consumption of processed foods, you will consume a wide variety of nutrients, as well as reduce your inflammatory load and exposure to xenoestrogens.
  • Include cruciferous vegetables daily. Cruciferous vegetables help to detoxify oestrogen through the liver due to their high level of indole-3-carbinole.

Stress Management

  • Find a method that works for you! This could be meditation, breathing exercises, physical exercise or a relaxing bath. Reducing stress will support the healthy production and regulation of hormones.

Nutritional Medicine

  • Work with a qualified practitioner to ensure you get the correct nutrient, correct form and a therapeutic dose for you.

The Importance of Seeking Professional Guidance

If any of these symptoms resonate with you, it is important to seek professional guidance so you can identify and treat your root cause. Generic hormone-balancing protocols and over-the-counter supplements can often make hormone imbalances worse, not better.

At Perth Health Collective, we can support you through functional testing and working alongside your GP so you can get the most from your blood tests. We work with you through a thorough analysis of your case and identify underlying drivers of oestrogen dominance to provide the right treatment plan for you. This will often include dietary and lifestyle modifications that work for you, nutritional medicine (supplements), and ongoing care and support.

Reach out to our friendly team of clinical nutritionists if you would like to know more or book a consultation.