13/03/2026
Most women think estrogen or progesterone are the most important hormones.
But the hormone that actually sits at the top of the hierarchy is cortisol.
Cortisol is the body’s master regulator.
It determines whether your body is in survival mode or safety mode.
And when cortisol signalling is off — whether too high or too low — every hormone underneath it is affected.
This is something I see over and over again on hormone testing.
When cortisol is dysregulated it can show up as:
• High cortisol output (wired, anxious, poor sleep)
• Low tissue cortisol (burnt out, exhausted, struggling to cope)
• Flattened cortisol rhythm across the day
• Poor morning cortisol activation
And when cortisol isn’t signalling properly, the body starts adjusting other systems to compensate.
This can lead to:
• Blood sugar instability
• Thyroid slowing down
• Estrogen dominance or poor estrogen clearance
• Low progesterone
• Increased inflammation
• Resistant weight gain
Because the body always prioritises survival over optimisation.
If the brain perceives stress — whether from emotional stress, inflammation, poor sleep, gut dysfunction, blood sugar crashes, or overtraining — cortisol will shift to manage that load.
Which is why focusing only on “balancing hormones” often misses the bigger picture.
If cortisol isn’t supported first, the downstream hormones struggle to regulate.
Some signs cortisol signalling may be off include:
• Waking tired
• Energy crashes in the afternoon
• Feeling wired but exhausted
• Poor stress tolerance
• Sleep issues (especially 2–3am waking)
• Brain fog
• Weight that won’t move despite doing everything “right”
The goal is not simply lowering cortisol.
The goal is restoring healthy cortisol rhythm and signalling.
When cortisol rhythm improves, the hormones underneath it often begin to self-correct.
Energy improves.
Sleep deepens.
Weight becomes easier to shift.
And the body moves back toward balance.
Because the body isn’t broken.
It’s responding to the signals it’s receiving.
— Lahna
Hormone Nurse
