Hormone Harmony: Phytoestrogens and Menopause

Phytoestrogens are plant compounds that are structurally and functionally similar to the oestrogen in our bodies.

We're still learning about their effects, but what we know so far is that they play a beneficial role in cardiovascular health, bone health and the relief of hot-flushes during menopause.

In terms of cancer risk, the research is still unclear with some studies showing phytoestrogens are protective against certain cancers whilst other studies show there is no significant protection.

In this blog I'm going to explore the role of phytoestrogens during menopause.

Before I start, here are a few examples of common phytoestrogens that you should be able to purchase in your local supermarket:

• Isoflavones - soybeans, tofu, tempeh, soy milk, edamame, chickpeas
• Lignans - flaxseeds, sesame seeds, whole grains
• Coumestans - alfalfa sprouts, pinto beans, split peas
• Stilbenes - red grapes, red wine 😀

What Do Phytoestrogens Do?

As mentioned earlier, phytoestrogens are similar to our body's natural oestrogen and can bind to oestrogen receptors on our cells, exerting either an oestrogenic or anti-oestrogenic effect depending on the circulating levels of oestrogen in the body. Oestrogen is not only a reproductive hormone - it also plays important roles in cardiovascular, bone and mental health.

When a woman reaches menopause her oestrogen levels drop significantly and this decline in oestrogen is what is thought to cause so many of her menopausal symptoms as well as increased risks of osteoporosis, heart disease and changes in mental health (for example brain fog, poor memory, depression, anxiety, and mood swings).

According to Mangione et al. (2022), women spend roughly 40% of their lives in the postmenopausal state. That's just under half their life!!! And who wants to spend so much of their life struggling with mental health problems, broken bones and heart disease? This is why it is vital to look at one's diet and take advantage of all that nature has to offer.

Phytoestrogens and heart health

The Western diet most often recommended to decrease one's risk of cardiovascular disease is the Mediterranean diet and numerous studies show that it has a positive impact on heart health. This diet is naturally high in phytoestrogens such as isoflavones and lignans. Other studies show that regularly eating phytoestrogens is associated with a reduction in total cholesterol levels, lower blood pressure and improved heart function (Desmawati and Sulastri, 2019).

Considering that heart disease in menopausal and postmenopausal women is 2 to 3 times higher than in women of reproductive age, it is vital that a woman at this age changes her diet to decrease her risk of developing a cardiovascular condition (Peacock et al., 2023). Including more phytoestrogens in her diet, or following the Mediterranean diet, can help reduce this risk.

Phytoestrogens and bone health

Oestrogen helps protect one's bones and when oestrogen levels decline during menopause, bone resorption increases and bone mineral density decreases. This means a post-menopausal woman is at an increased risk of fracturing a bone or developing osteoporosis.

Studies on the efficacy of phytoestrogens in bone health give inconsistent results but in a recent meta-analysis of randomized controlled trials Inpan et al. (2024) concluded that isoflavones effectively enhance bone mineral density in postmenopausal women. In this study, they did however emphasise that at least 50mg/day of the isoflavone genistein needs to be consumed.

Phytoestrogens and menopausal symptoms

Unfortunately, phytoestrogens don't help menopausal symptoms such as increased urinary tract infections or vaginal dryness. However, there are many clinical studies as well as anecdotal evidence showing that they can help a woman cope better with hot flushes. Again, as with studies on bone health, studies on hot flushes also emphasise a minimum of 50mg/day needs to be eaten.

Phytoestrogens and breast cancer

Women who have had breast cancer are sometimes wary of eating phytoestrogens but a study of 9514 breast cancer survivors who were tracked for 7 years showed there was no association between post-diagnosis soy intake and tumour recurrence (Messina, 2014). Other studies, also show there is no association between consuming phytoestrogens and changes to breast or endometrial tissue (Desmawati and Sulastri, 2019).

If you're feeling a little stuck on how to include more phytoestrogens in your diet, or on how to adjust your diet for menopause, then subscribe to my blog below and you'll get access to my subscriber's only page where you'll find downloadable self-help guides on these topics.

References:

Chen, M. N., Lin, C. C., & Liu, C. F. (2015). Efficacy of phytoestrogens for menopausal symptoms: a meta-analysis and systematic review. Climacteric : the journal of the International Menopause Society, 18(2), 260–269. https://doi.org/10.3109/13697137.2014.966241

Desmawati, D., & Sulastri, D. (2019). Phytoestrogens and Their Health Effect. Open access Macedonian journal of medical sciences, 7(3), 495–499. https://doi.org/10.3889/oamjms.2019.044

Inpan, R., Na Takuathung, M., Sakuludomkan, W., Dukaew, N., Teekachunhatean, S., & Koonrungsesomboon, N. (2024). Isoflavone intervention and its impact on bone mineral density in postmenopausal women: a systematic review and meta-analysis of randomized controlled trials. Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA, 35(3), 413–430. https://doi.org/10.1007/s00198-023-06944-y

Mangione, C. M., Barry, M. J., Nicholson, W. K., Cabana, M., Caughey, A. B., Chelmow, D., Coker, T. R., Davis, E. M., Donahue, K. E., Jaén, C. R., Kubik, M., Li, L., Ogedegbe, G., Pbert, L., Ruiz, J. M., Stevermer, J., & Wong, J. B. (2022). Hormone Therapy for the Primary Prevention of Chronic Conditions in Postmenopausal Persons: US Preventive Services Task Force Recommendation Statement. JAMA, 328(17), 1740–1746. https://doi.org/10.1001/jama.2022.18625

Messina M. (2014). Soy foods, isoflavones, and the health of postmenopausal women. The American journal of clinical nutrition, 100 Suppl 1, 423S–30S. https://doi.org/10.3945/ajcn.113.071464

Peacock K, Carlson K, Ketvertis KM. Menopause. [Updated 2023 Dec 21]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK507826/

Please note: The health and nutritional information provided by Ruth Hull and/or this blog is intended for general educational purposes only. You should not rely on this information as a substitute or replacement for professional medical advice, diagnosis or treatment. If you have any concerns regarding your health and before making any changes to your lifestyle or diet you should always consult your general medical practitioner or other health professional.