Understanding Oestrogen Metabolism: Why It Matters in breast and prostate Cancer

Oestrogen is a vital hormone, but how your body processes and clears it matters, especially for breast cancer prevention, recurrence risk, and hormone balance. Our liver plays a central role through a two-step detox process:

Phase I: Activation (Cytochrome P450 Enzymes)

During Phase I, our liver alters oestrogen molecules to facilitate their elimination. It transforms oestrogen into metabolites, some of which are beneficial, while others may pose risks:

•  2-OH oestrogen (offers protection)

•  4-OH oestrogen (may harm DNA)

•  16-OH oestrogen (can promote cell growth)

The aim is to promote the 2-OH pathway as this metabolite is linked to a reduced risk of breast cancer.

Phase II: Conjugation (Neutralization & Elimination)

During Phase II, your liver prepares the metabolites for safe expulsion via bile and urine. This process includes methylation, sulfation, and glucuronidation, which are complex ways your body & "labels" oestrogen for disposal. If not properly supported, harmful metabolites from Phase I may persist or recirculate, particularly if the gut or detoxification pathways are slow.

How to Support Oestrogen Metabolism Through Food & Lifestyle

Eating Cruciferous Vegetables (Broccoli, Kale, Cauliflower, Cavolo nero)

•  High in indole-3-carbinol and sulforaphane

•  Aid Phase I by promoting the 2-OH pathway

•  Stimulate detoxification enzymes and protect DNA

Tip - try our cumin cauliflower, quinoa and kale salad

Flaxseeds

Rich in lignans, which can help regulate oestrogen levels and absorb excess in the gut. Eating might lower the risk of recurrence in breast cancer survivors

Tip- Add 1–2 tbsp ground flax to pancake batter, oats, or smoothies

Fill up on Fibre

Supports oestrogen elimination by binding it in the gut and preventing reabsorption. Aim for at least 30g–35g/day (from vegetables, legumes, seeds, whole grains) – most people in the UK only eat 19g a day.

Tip: Track fibre for a week to build awareness

Lifestyle Support

• Hydration: Helps flush out oestrogen via urine and stool

• Sweating: Saunas, exercise, or movement aid gentle detox

• Gut Health: A healthy microbiome prevents estrobolome disruption (the gut bacteria

• involved in oestrogen recycling)

• Sleep: Your liver detoxifies most effectively at night — aim for 7–9 hours

• Avoid Toxins: Reduce xenoestrogen exposure (plastics, fragrances, pesticides)

  
  

Supporting both Phase I and II detox helps your body to:

•  Metabolise oestrogen safely

•  Reduce the build-up of harmful oestrogen forms

•  Lower inflammation and hormone-driven cancer risk

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Genomic DNA testing provides valuable information on how your body manages and removes toxins, such as oestrogen. By examining specific gene variations known as SNPs, we can gain a clearer understanding of the efficiency of your detoxification pathways and tailor your support to meet your individual needs. When working with one-to-one patients, I often use genomic testing to personalise their diet and lifestyle. Find out more here.