Hormone imbalance can affect various aspects of health, including mood, energy, menstrual cycles, fertility, and overall well-being. In this practitioner deep dive blog, our Nutritional Therapist Annie will consider the use of certain nutrients to support oestrogen balance specifically, so that you can help your clients take control of their hormonal health.

What is ‘oestrogen dominance’?

The concept of “oestrogen dominance” is often misunderstood and does not necessarily mean excessively high oestrogen levels. Rather, it describes an imbalance between oestrogen and progesterone, which may occur due to increased oestrogen production, insufficient progesterone, or exposure to xenoestrogens and endocrine disruptors. Common hormone-related conditions where poor oestrogen balance may contribute include PMS, PMOS (Polyendocrine metabolic ovarian syndrome, formally known as PCOS), fibroids, certain cancers, and endometriosis. Addressing oestrogen dominance isn’t about suppressing oestrogen; it’s about restoring balance and supporting the body to produce, metabolise, and eliminate hormones appropriately.

What causes ‘oestrogen dominance’?

Poor hormone metabolism and detoxification via the liver and gut, chronic stress contributing to the suppression of progesterone production, and times of hormonal changes such as perimenopause, can all influence balance. Diet and lifestyle factors, such as low fibre intake, dysregulated blood sugar balance, high alcohol consumption, and ultra-processed foods, can all contribute. Higher body fat levels can increase oestrogen production, and exposure to environmental oestrogen-like compounds (xenoestrogens), found in plastics, pesticides, and personal care products, can further exacerbate oestrogen dominance.

What are phytoestrogens?

Phytoestrogens are naturally occurring plant compounds that have a similar structure to oestrogen, meaning they can interact with oestrogen receptors in the body, producing an oestrogen-like effect. When oestrogen levels are low (such as during menopause), phytoestrogens can gently mimic oestrogen and help support balance. When levels are higher, they can compete with natural oestrogen for receptor binding, potentially helping to reduce overall oestrogenic activity. This may be beneficial in cases of oestrogen dominance because phytoestrogens are generally weaker than the body’s own oestrogen. By competing for oestrogen receptor binding, they may help reduce the overall strength of estrogenic stimulation in tissues. In effect, they can act as selective oestrogen modulators, gently balancing oestrogen activity rather than simply increasing it. This may help support symptoms associated with excess oestrogen exposure, such as heavy periods, breast tenderness, PMS, and hormonal fluctuations.

Nutrients for hormonal balance

Broccoli

Broccoli contains several important nutrients, vitamins, and minerals as well as bioactive compounds such as glucosinates, sulforaphane, and indole-3-carbinol (I3C), which have potent antioxidant and anti-inflammatory effects. I3C in particular has been found to induce cytochrome-P450-dependent metabolism of oestrogen. (Syed, 2023)

Certain phytoestrogen-rich foods, particularly cruciferous vegetables such as broccoli support both phase 1 and phase 2 of liver detoxification and also provide I3C and sulforaphane. (Gasmi, 2026)​ These compounds support healthy oestrogen metabolism and detoxification by promoting the clearance of excess or waste oestrogen and reducing the potential for recirculation in the body. They may also help encourage oestrogen metabolism down the more favourable 2-hydroxylation pathway (2-OH), reducing conversion through the more proliferative 16-hydroxylation pathway (16-OH), thereby improving the 2:16 oestrogen metabolite ratio. Oestrogen is metabolised primarily via the 2-OH, 4-OH, and 16-OH pathways. The 2-OH pathway is generally regarded as the more favourable route, whereas increased activity through the 16-OH pathway has been associated with greater estrogenic stimulation and proliferative effects in tissues. The 4-OH pathway is also considered less desirable due to the potential formation of more reactive metabolites. (Fowke, 2000; Fahey 2025)​

Sulforaphane also activates the Nrf2 pathway, enhancing the production of antioxidant and detoxification enzymes involved in the conjugation and elimination of oestrogen metabolites. By supporting detoxification, reducing oxidative stress, and modulating inflammatory pathways, these compounds may help address metabolic and hormonal shifts. (Saito, 2025)

Rosemary

Like broccoli and other cruciferous vegetables, rosemary may also help support balanced oestrogen metabolism by influencing the pathways through which oestrogen is metabolised in the body. Pre-clinical research suggests that rosemary may favour metabolism via the more protective 2-OH pathway, while reducing metabolism through the more proliferative 16-OH pathway. (Fahey, 2025)

Rosemary also exhibits a wide range of biological activities, including antimicrobial, anti-inflammatory, antioxidant, anti-apoptotic, anti-tumorigenic, analgesic, and neuroprotective effects. Research suggests rosemary may positively influence mood, cognitive function, memory, pain perception, anxiety, and sleep quality. (Rahbardar, 2020) Its antioxidant, detoxifying, and anti-inflammatory properties may also support neuroprotection and cognitive performance (Kosmopoulou, 2024), making it a promising herb for individuals experiencing brain fog, cognitive fatigue, or stress-related cognitive symptoms.

Furthermore, rosemary has also been shown to exhibit anti-androgenic activity through inhibition of 5-alpha reductase, the enzyme responsible for converting testosterone into dihydrotestosterone (DHT). Elevated DHT levels are associated with androgenic hair loss and scalp follicle miniaturisation. Reducing this conversion may help support hair density and reduce hair shedding in susceptible individuals. (Maruta, 2013)

Calcium d-glucarate

The oestrobolome refers to the subset of the gut microbiome involved in oestrogen metabolism, encompassing bacterial genes capable of metabolising and modulating circulating oestrogens. Increasing research highlights the bidirectional relationship between gut microbial composition and hormone homeostasis, with the oestrobolome playing a central role in the regulation of oestrogen circulation, detoxification, and excretion. (Ervin, 2019)‌

Phase II liver detoxification is responsible for neutralising toxins, metabolic byproducts, and hormones, including oestrogen, to facilitate their safe elimination from the body. One of the key phase II pathways involved in oestrogen clearance is glucuronidation, whereby oestrogen metabolites are conjugated to glucuronic acid in the liver and excreted via the bile into the gastrointestinal tract for elimination through the stool. This process highlights the importance of optimal liver function, gut microbiome balance, and regular bowel motility in maintaining healthy oestrogen metabolism.

Certain gut bacteria produce the enzyme beta-glucuronidase, which can deconjugate oestrogen metabolites within the intestine, allowing free oestrogen to be reabsorbed back into circulation via enterohepatic recirculation rather than excreted. Dysbiosis, low microbial diversity, constipation, inflammatory gut states, and diets low in fibre may all contribute to elevated beta-glucuronidase activity, potentially increasing circulating oestrogen burden and contributing to symptoms associated with oestrogen dominance, including PMS, heavy or painful periods, breast tenderness, fibroids, and endometriosis. This demonstrates the close interrelationship between gut health, detoxification capacity, and hormonal balance. (Thomson, 2016)

Calcium d-glucarate (CDG) is a calcium salt made from calcium and D-glucaric acid, a compound that is found in many fruits and vegetables that supports liver detoxification pathways and inhibits beta-glucuronidase activity. When taken via supplementation, CDG becomes D-glucaric acid, from which D-glucaro-1,4-lactone is derived, which is what inhibits beta-glucuronidase, to promote the elimination of glucuronides. (Ayyadurai, 2023)

Red Clover

Red clover contains the isoflavone methoxy ethers, formononetin and biochanin A, as well as smaller amounts of genistein, daidzein, glycitein, and prunetin. These isoflavones are structurally similar to endogenous 17β-estradiol and can interact with oestrogen receptors, appearing to show a greater affinity for ER-β than ER-α. The former is more closely linked to bone, brain, and cardiovascular health, while ER-α is associated with stronger stimulation of breast and reproductive tissues. This selective activity may allow red clover isoflavones to provide some menopause-related benefits with a milder oestrogen-like effect. Numerous studies have reported a significant reduction in menopausal symptom severity, in particular the frequency of hot flushes. (Kanadys, 2021)

Emerging research has also highlighted potential roles for red clover in supporting blood glucose regulation, lipid metabolism, cardiovascular health, bone health in osteoporosis and osteopenia, and cognitive function. (Zukić, 2024) In addition, red clover extract and the isoflavones genistein and biochanin A appear to influence lipid metabolism through mechanisms that are not solely dependent on oestrogen receptor activity. It is also suggested that they may increase PPAR-α expression and activate AMPK signalling pathways, thereby enhancing the expression of genes involved in fatty acid oxidation and lipoprotein metabolism. (Błaszczuk, 2022) Phytoestrogens from red clover have antioxidant activity and interact with transcription factors such as NF-κB. Furthermore, it is indicated that they have protective effects on osteoporosis and the cardiovascular system. ​(Beck, 2005)​

Research suggests that higher dietary intake of isoflavones has been associated with a reduced risk of endometriosis. (Yoiseflu, 2019) Genistein and daidzein have been studied for their role in suppressing the progression of endometriosis. (Cai, 2021)

NAC

N-acetyl cysteine (NAC) may support healthy oestrogen balance through its role in oxidative stress and liver detoxification. NAC acts as a precursor to glutathione, one of the body’s primary antioxidants, which is involved in phase II detoxification pathways responsible for the conjugation and elimination of oestrogen metabolites. By supporting glutathione production, reducing oxidative stress, and aiding the clearance of excess or reactive oestrogen metabolites, NAC may help promote more balanced oestrogen metabolism and overall hormonal health. Its antioxidant and anti-inflammatory properties have also led to research into its potential applications in hormone-related conditions, including PMOS and endometriosis, where oxidative stress and chronic inflammation are central drivers. (Manokaran, 2022) NAC has been found to decrease total testosterone levels and increase follicle-stimulating hormones (FSH) (Shahveghar, 2023) and has significant effects on progesterone, endometrial thickness, and luteinising hormone (LH). (Vina, 2025)

Vitamin B6

B vitamins play a central role in methylation and neurotransmitter production, influencing key aspects of health, including mood regulation, anxiety, energy levels, cognitive function, and cardiovascular health. They also support homocysteine metabolism, DNA synthesis, and nervous system function, all of which are important for hormonal balance. (Keller, 2019) After oestrogen is metabolised, it needs to be methylated, which is dependent on catechol-o-methyltransferase (COMT), an enzyme that requires B6 and magnesium as cofactors to work effectively. Lower levels of B6, B12, or folate can impact methylation and impair the conversion of homocysteine to methionine, leading to elevated homocysteine concentrations. This enhances the generation of reactive oxygen species (ROS) through processes such as homocysteine auto-oxidation and the inhibition of key antioxidant enzymes, including glutathione peroxidase and superoxide dismutase, increasing the risk of cognitive decline and neurodegenerative disease. (Lauer, 2022) B6 is also needed to regulate prolactin and in the production of progesterone, supporting oestrogen to progesterone balance. (Briden, 2018)

Conclusion

Supporting healthy oestrogen balance requires a multifactorial approach that considers not only hormone production, but also hormone metabolism and detoxification. Nutrients, including CDG, red clover, and broccoli, such as those found in our new Oestro-Balance, may offer valuable support for those looking to balance their hormonal health.

References

• Beck, V., et al (2005). Phytoestrogens derived from red clover: An alternative to estrogen replacement therapy? The Journal of Steroid Biochemistry and Molecular Biology, 94(5), 499–518.
• Błaszczuk, A., et al. (2022). Role of phytoestrogen-rich bioactive substances (Linum usitatissimum L., Glycine max L., Trifolium pratense L.) in cardiovascular disease prevention in postmenopausal women: A systematic review and meta-analysis. Nutrients, 14(12), 2467.
• Briden, L. (2018). Period repair manual: Natural treatment for better hormones and better periods (2nd ed.). Pan Macmillan Australia.
• Cai, X., et al. (2021). Phytoestrogens for the management of endometriosis: Findings and issues. Pharmaceuticals, 14(6), 569.
• Ervin, S et al., (201) Gut microbial β-glucuronidases reactivate estrogens as components of the estrobolome that reactivate estrogens, Journal of Biological Chemistry, Volume 294, Issue 49, Pages 18586-18599,
• Fahey, J. W., & Raphaely, M. (2025). The impact of sulforaphane on sex-specific conditions and hormone balance: A comprehensive review. Applied Sciences, 15(2), 522.
• Fowke, J. H., et al. (2000). Brassica vegetable consumption shifts estrogen metabolism in healthy postmenopausal women. Cancer Epidemiology, Biomarkers & Prevention, 9(8), 773–779.
• Gasmi, A., Noor, S., et al. (2026). Broccoli and other botanicals in the prevention and treatment of premenstrual syndrome. Current Medicinal Chemistry, 33.
• Ghasemzadeh Rahbardar, M., & Hosseinzadeh, H. (2020). Therapeutic effects of rosemary (Rosmarinus officinalis L.) and its active constituents on nervous system disorders. Iranian Journal of Basic Medical Sciences, 23(9), 1100–1112.
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• Shahveghar Asl, et al (2023). The effects of N-acetylcysteine on ovulation and sex hormones profile in women with polycystic ovary syndrome: A systematic review and meta-analysis. The British Journal of Nutrition, 130(2), 202–210.
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• Thomson, C., et al. (2016). Chemopreventive properties of 3,3′-diindolylmethane in breast cancer: Evidence from experimental and human studies. Nutrition Reviews, 74(7), 432–443.
• Viña, I., et al. (2025). Efficacy of N-acetylcysteine in polycystic ovary syndrome: Systematic review and meta-analysis. Nutrients, 17(2).
• Youseflu, S., Set al.(2019). Dietary phytoestrogen intake and the risk of endometriosis in Iranian women: A case-control study. International Journal of Fertility & Sterility, 13(4), 296.
• Zhu, B. T., et al. (1998). Dietary administration of an extract from rosemary leaves enhances the liver microsomal metabolism of endogenous estrogens and decreases their uterotropic action in CD-1 mice. Carcinogenesis, 19(10), 1821–1827.
• Zukić, M., et al. (2024). Effectiveness of commercial red clover (Trifolium pratense L.) products for the treatment of symptoms in menopausal women—A narrative review. Nutraceuticals, 4(3), 430–449.

All of our blogs are written by our team of expert Nutritional Therapists. If you have questions regarding the topics that have been raised, or any other health matters, please do contact them using the details below:

nutrition@cytoplan.co.uk

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