Words like « phyto-oestrogens » or « oestrogen-like » can sometimes be alarming, as they are often misunderstood. It is essential to distinguish between substances that stimulate oestrogenic impregnation and those that reduce it. In this article, we will clarify this point by focusing on a very interesting mechanism: the SERM effect.

What exactly is a SERM?

SERM stands for Selective Estrogen Receptor Modulator. Simply put, these are molecules that resemble oestrogens (they have an analogous structure), but do not have quite the same action. They bind to cellular oestrogen receptors, taking the place of natural oestrogens such as oestradiol. By blocking these receptors, they prevent the actual oestrogens from binding and acting fully.

The result? A modulation of oestrogen action. These molecules do not activate receptors as powerfully as oestradiol would. They are therefore very interesting for women suffering from hyper-oestrogenism, as they reduce the action of oestrogens and thus the undesirable effects linked to their excess.

Why is this relevant in menopause?

The SERM effect is also relevant for menopausal women. Once menopause is well established, oestrogen production drops considerably, and some women may experience undesirable effects from this drop. This is where molecules with a SERM effect come in. Although their impact is mild, they stimulate oestrogen receptors, offering a gentle and natural activation of the receptors. This activation is much weaker than that of oestrogens themselves, but it can nevertheless provide appreciable comfort for menopausal women.

Soy and flaxseeds: champions of the SERM effect

Fermented soy: miso and company

Soy is known for its phyto-oestrogens, but not all soy-derived products are equal. It is fermented soy, particularly in the form of miso, that is most interesting. The fermentation of soy potentiates the SERM effect thanks to the isoflavones it contains, which partially activate oestrogen receptors.

Miso is therefore an excellent choice for women with hyper-oestrogenism or in menopause, as it helps modulate oestrogenic impregnation whilst adding a delicious touch to your diet.

Practical tip: To get all the benefits, choose unpasteurised miso and add it to cold preparations or at the end of cooking to preserve its beneficial enzymes. You can incorporate it into hummus, dips, soups, and more.

Flaxseeds: even more powerful allies

If soy is effective, flaxseeds are even more so! They block oestrogen receptors even more strongly than soy.

Tips to maximise their benefits:

• Always grind flaxseeds before consuming them, as whole seeds don’t release their active compounds.
• Store ground flaxseeds in the refrigerator, as they are rich in omega-3 fatty acids which deteriorate quickly at room temperature.

Usage ideas: Sprinkle them on salads, soups, or add them to smoothies. One tablespoon per day is enough to benefit from their protective effects.

⚠️ This does not apply to linseed oil, which, although rich in omega-3, does not contain these phyto-hormones.

How to incorporate them into your diet?

Integrating these SERM-effect foods into your diet is simpler than it seems:

Miso

• In addition to replacing salt, you can add a spoonful of miso to your soups or sauces.
• Use it to prepare vinaigrettes or dips.
• Unpasteurised miso must be added at the end of cooking for hot dishes, or directly into cold preparations.

Ground flaxseeds

• They pair perfectly with savoury dishes such as salads, roasted vegetables, or morning smoothies.
• Make sure to grind them just before consumption, or store them ground in the refrigerator.

Tip: No special equipment needed to grind your flaxseeds — a good-quality pepper mill will do the trick!

Conclusion

Whether you are in a phase of hyper-oestrogenism or in menopause, the SERM effect can play a key role in your hormonal wellbeing. It helps regulate oestrogenic impregnation by partially blocking oestrogen receptors in women with excess, or by gently stimulating these receptors in women with oestrogen deficiency.

By incorporating foods such as fermented soy and flaxseeds into your diet, you can support your hormonal balance naturally, These are allies I regularly recommend in my consultations in Liège and online.

⟶ Further reading: Functional Health and PERMANUTRITION · Night Sweats: Hormonal Mechanisms · Ovulation: a Mirror of Women’s Health · Satiety and Hormones