The Nervous System Diaries
Cortisol is a steroid hormone produced by the adrenal glands. It is essential for survival. It mobilizes energy, regulates metabolism, suppresses inflammation, and helps the body respond to stress.
But when cortisol sticks around too long—when the relationship becomes chronic—it starts to cause damage. Like many toxic romances, it begins with passion and ends with exhaustion.
Today, we are going to explore how cortisol works, how it becomes dysregulated, and how to repair the relationship before your nervous system files a restraining order.
[Segment 1: What is Cortisol]
Cortisol is a glucocorticoid hormone synthesized in the adrenal cortex in response to a signal cascade known as the hypothalamic-pituitary-adrenal axis, or HPA axis.
The sequence looks like this:
- Stress detected (physical, emotional, psychological)
- Hypothalamus releases corticotropin-releasing hormone (CRH)
- Pituitary gland releases adrenocorticotropic hormone (ACTH)
- Adrenal glands release cortisol
Once in circulation, cortisol travels through the bloodstream and binds to glucocorticoid receptors in nearly every tissue in the body.
It prepares the body to respond to stress by:
- Increasing blood glucose through gluconeogenesis
- Suppressing immune and inflammatory responses
- Enhancing memory consolidation
- Contributing to alertness and arousal
In short: cortisol is your body’s chemical call to action.
[Segment 2: Cortisol in Acute vs. Chronic Stress]
Acute stress is adaptive. Cortisol spikes briefly, support performance, and then declines. It helps you respond to a deadline, a physical threat, or a moment of emotional intensity.
The problem begins when stress becomes chronic.
In chronic stress:
- The HPA axis remains activated.
- Cortisol remains elevated or becomes dysregulated.
- The body enters a state of persistent alertness, which taxes multiple systems.
This is not sustainable. Over time, the “relationship” turns toxic.
[Segment 3: Cortisol’s Long-Term Effects]
Persistent high cortisol affects nearly every system in the body:
- Nervous System
- Impaired neurogenesis, especially in the hippocampus
- Memory problems, brain fog, difficulty concentrating
- Heightened amygdala activity, increasing fear and anxiety
- Inhibited prefrontal cortex, reducing decision-making and impulse control
- Immune System
- Suppression of T-cell function
- Increased susceptibility to infection
- Greater inflammation due to glucocorticoid resistance over time
- Endocrine and Metabolic Systems
- Disrupted insulin sensitivity
- Increased visceral fat accumulation
- Disrupted thyroid function
- Menstrual irregularity or low testosterone
- Cardiovascular System
- Hypertension
- Increased risk of atherosclerosis
- Elevated resting heart rate
This is why cortisol is often called a catabolic hormone—it breaks down tissues, resources, and internal equilibrium under long-term exposure.
[Segment 4: Signs of Cortisol Dysregulation]
Signs that your cortisol rhythm may be dysfunctional include:
- Fatigue in the morning, alertness at night (reversed circadian rhythm)
- Reliance on caffeine to feel normal
- Mid-afternoon energy crashes
- Insomnia or light, unrefreshing sleep
- Anxiety, irritability, or emotional volatility
- Cravings for sugar, salt, or fat
- Suppressed immune function or slow recovery from illness
[Segment 5: Restoring Cortisol Balance]
The goal is not to eliminate cortisol. That would be biologically catastrophic. The goal is rhythmic regulation—restoring healthy circadian cycling and stress reactivity.
- Prioritize Sleep
Cortisol should be low at night and rise in the early morning. Exposure to blue light, caffeine, and late-night rumination disrupts this pattern. Aim for consistent sleep and waking times. Avoid screens 60 minutes before bed. - Light Exposure
Morning sunlight stimulates cortisol release at the correct time. Get 5–15 minutes of direct natural light in your eyes within one hour of waking. This anchors the circadian rhythm. - Blood Sugar Regulation
Unstable glucose causes cortisol to spike. Eat protein- and fat-rich meals at regular intervals. Avoid excessive refined sugar or skipping meals. - Movement—but Not Overtraining
Moderate aerobic exercise lowers baseline cortisol. However, excessive or high-intensity training without rest can keep cortisol elevated. Find balance. - Nervous System Regulation
Use techniques to shift out of sympathetic dominance:
- Breathwork (e.g., box breathing, 4-7-8 breathing)
- Meditation
- Body scans
- Time in nature
- Laughter, play, and positive social interaction
- Address Psychological Stressors
Chronic cortisol elevation is often not about what is happening now, but what has never been resolved. Cognitive behavioral therapy, trauma-informed care, and internal family systems work can reduce chronic threat perception and HPA overactivation.
[Conclusion]
Cortisol is not the villain. It is a first responder. The issue arises when the alarms never stop ringing—when your body forgets how to return to baseline.
This toxic romance begins with protection and ends with exhaustion. But it can be healed.
You can retrain your brain. You can reset your rhythm. You can reclaim energy, focus, and emotional balance.
The stress response is ancient. But so is your capacity to recover.
End the toxic romance. Love your nervous system.
And break up with panic.
