Female hormones: the user manual

Estrogen, progesterone, cortisol, testosterone, thyroid hormones: these messengers govern energy, mood, weight and libido. This hub explains how they work, and what happens when their balance changes after 40.

What your hormones do, concretely

Estrogen, progesterone, testosterone, cortisol, thyroid hormones: these messengers circulate in very small amounts and yet steer energy, mood, sleep, bone density, fat distribution and libido. After forty, their balance changes, and it rarely changes in a linear way.

Estrogen is not just for reproduction

This is the most underestimated point. Receptors for sex hormones are present in a great many tissues: bones, blood vessels, brain, mucous membranes, joints. The most telling argument comes from a particular clinical situation: aromatase inhibitors, prescribed after hormone-dependent breast cancer, deliberately collapse estrogen levels, and a meta-analysis of twenty-one studies covering more than thirteen thousand women finds that about 46% of them develop joint pain (PMID 28204994). Be careful not to overinterpret: this is a sudden, artificial hormonal drop, in women who have often been treated by chemotherapy. That figure does not carry over to natural menopause.

And hormones do not explain everything

The counterpoint is just as important. A review published in Osteoarthritis and Cartilage in 2024 points out that the differences between girls' knees and boys' knees (cartilage, meniscus, cruciate ligament) are visible from childhood, and that these differences "are not explained by sex hormones alone" (PMID 38703811). Be wary of content that brings everything back to a "hormonal imbalance": it is a convenient shortcut, rarely accurate.

What hormone testing can, and cannot, tell you

In perimenopause, a single measurement has limited value: levels fluctuate from one day to the next. The diagnosis remains clinical. On the other hand, some targeted tests have real value when the picture is misleading: that is notably the case for thyroid testing, because hypothyroidism shares many symptoms with menopause. It is up to the doctor to decide what is useful, based on your history.

The concepts to set aside

"Adrenal fatigue" is not recognized by any endocrinology society. Cleanses that promise to "rebalance hormones" have no basis. And a supplement that claims to act on estrogen without medical supervision raises exactly the same safety questions as a medication, without the oversight that goes with it.

This page is educational. No hormone treatment should be started, changed or stopped without the advice of the professional who knows your file.

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