Everyone’s Talking About Cortisol.... But Context Is Everything!

Cortisol has become the hormone of the moment. It’s blamed for everything from belly fat and burnout to brain fog and broken sleep. And while cortisol does play a central role in all of those issues, the real problem isn’t cortisol itself, it’s the lack of context around how it works.

Because here’s the truth: the way you support cortisol depends entirely on what’s driving the dysregulation. Without that understanding, you could be using the wrong strategy at the wrong time and doing more harm than good.

Cortisol in Context - What Is the HPA Axis and Why Does It Matter?

To understand cortisol, we need to start with the system that controls it: the HPA axis. This stands for Hypothalamic–Pituitary–Adrenal axis; a communication loop between your brain and adrenal glands that regulates how your body responds to stress.

Here’s how it works:

• The hypothalamus (in the brain) senses stress and signals the pituitary gland.

• The pituitary then tells your adrenal glands (just above your kidneys) to release cortisol.

• Cortisol then travels through the body to help manage the stressor raising blood sugar, increasing alertness, and altering immune responses as needed.

This system is brilliant in the short term. But when stress is constant from poor sleep, under-eating, emotional strain, over-exercising, or even low-grade inflammation the HPA axis can become overworked and start to dysregulate.

This doesn’t happen overnight. The breakdown happens in phases, and each phase looks, feels, and functions differently.

The Four Phases of HPA Axis Dysfunction

Understanding which stage, you are in is essential for selecting the right nutritional and lifestyle interventions.

Phase 1: Balanced (Resilient State)

Cortisol and DHEA are in harmony. Energy is stable, you recover well, sleep is sound, and stress doesn’t knock you off course. This is a sign of a well-regulated HPA axis.

Phase 2: Acute Stress (High Cortisol)

The body is in ‘fight or flight’ mode. Cortisol is high, and DHEA tries to keep up. You might feel wired, edgy, struggle to sleep, and reach for caffeine to stay on top of things. This phase is adaptive but temporary.

Research shows that prolonged high cortisol is associated with increased abdominal fat, insulin resistance, and mood changes (Björntorp & Rosmond, 2000).

Phase 3: Compensatory Phase (Wired and Tired)

Cortisol and DHEA start to fall. You’re tired but can’t switch off. Mood dips, sleep worsens, and motivation crashes. This is often when people say, “I’m exhausted but I can’t relax.” You’re running on empty.

This stage is often linked with chronic inflammation, disrupted circadian rhythm, and immune dysfunction (Guilliams & Edwards, 2010).

Phase 4: Exhaustive Phase (Burnout)

Cortisol and DHEA are flatlined. Everything feels heavy: getting out of bed, concentrating, even low-impact exercise. The system is in ‘shutdown’ mode, state linked with chronic fatigue, depression, and low resilience to stress (Fries et al., 2005).

Why Guesswork Doesn’t Work

Most people have no idea they’re moving through these stages until symptoms pile up. And yet the supplements and strategies that support someone in Phase 2 might be completely wrong in Phase 4.

For example:

• Stimulating adaptogens like Rhodiola may benefit someone with low resilience and low cortisol but can worsen symptoms in someone already over-producing it.

  
  

• Meditation and rest might feel frustrating and ineffective in early hyper-cortisol phases if blood sugar is unstable and sleep is fragmented.

This is why context matters and why personalised, phase-specific support is crucial.

Functional Testing: When and Why to Use It

If you want clarity, test your cortisol rhythm. Functional hormone testing gives us insight into:

• Total cortisol output across the day (not just a single snapshot)

• The shape of the cortisol curve, high, flat, inverted?

• DHEA levels and cortisol-to-DHEA ratio

• Cortisol metabolites and clearance (in DUTCH testing)

Two of the most clinically useful options are:

• Salivary cortisol testing (4-point throughout the day)

• DUTCH Complete dried urine test

This data helps determine the phase of dysfunction and tailor your nutritional, supplement, and lifestyle plan accordingly, moving beyond symptom-chasing to targeted, root-cause support.

Final Thoughts

Cortisol is not the villain. It’s a vital hormone that keeps us alive, alert, and adaptive until it becomes dysregulated. Supporting it properly requires understanding the phase of HPA axis dysfunction you're dealing with.

Rather than applying generic “stress support” strategies, we must assess the full clinical picture, biochemistry, symptom history, lifestyle stressors, and resilience to provide meaningful, long-term change.

Ready to stop guessing and start testing?

I offer 1:1 functional testing consultations using salivary or DUTCH hormone profiles, with tailored nutrition and lifestyle plans based on your results.

Book a free call here or get in touch for more details.

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References

• Björntorp, P., & Rosmond, R. (2000). Obesity and cortisol. Nutrition, 16(10), 924–936.

• Fries, E., Hesse, J., Hellhammer, J., & Hellhammer, D.H. (2005). A new view on hypocortisolism. Psychoneuroendocrinology, 30(10), 1010–1016.

• Guilliams, T.G., & Edwards, L. (2010). Chronic stress and the HPA axis: clinical assessment and therapeutic considerations. The Standard, 9(2), 1–12.