When the Threat Does Not Go Away
Adrenaline is fast but it does not last long. If the stress continues, your body shifts into a longer-term gear. The hypothalamus releases something called CRH (corticotropin-releasing hormone), which tells the pituitary gland to release ACTH, which signals the adrenal glands to produce cortisol.
Cortisol is the hormone people tend to hear about when they read about stress. It keeps you alert. It breaks down stored energy so your muscles have fuel. It suppresses inflammation in the short term so your body can focus on the perceived threat.
In a healthy stress response, cortisol peaks within about 10 to 30 minutes and then tapers off through a feedback loop. The brain detects the elevated cortisol and dials back the alarm. The system resets. Research on this feedback process, including work by Shields and Slavich (2017), has shown that when this loop works properly, the body returns to baseline relatively quickly.
But when the stressor does not go away, the loop never completes. And that is where the trouble starts.
What Chronic Stress Actually Does to Your Body
When cortisol stays elevated for weeks or months, it stops being helpful and starts causing damage. The system that was designed to protect you begins to work against you.
Your immune system is one of the first things affected. Short bursts of cortisol can temporarily reduce inflammation, which makes sense if you are running from a bear and need your body focused on escape, not healing a scraped knee. But sustained cortisol exposure does the opposite. It dysregulates the immune system and can actually increase chronic low-grade inflammation throughout your body.
A review published in Psychosomatic Medicine by Rohleder (2014) found that chronic psychosocial stress is linked to elevated inflammatory markers like IL-6, which plays a role in conditions ranging from cardiovascular disease to autoimmune disorders.
Your brain chemistry shifts too. Under acute stress, your brain produces more glutamate, an excitatory neurotransmitter that sharpens focus. That is useful in a crisis. But chronic stress can reduce the production of calming neurotransmitters like GABA and serotonin. The result is a nervous system that is always running hot and a brain that has trouble settling down. That is when the anxiety starts to feel constant, the sleep falls apart, and the ability to concentrate disappears.
Why This Shows Up the Way It Does
I see the effects of chronic stress in my office every week. Clients come in describing anxiety that will not respond to deep breathing. Depression that medication has not fully touched. Irritability that is ruining their relationships. Exhaustion that eight hours of sleep does not fix.
Most of them do not connect what they are feeling to stress. It has been going on so long it just feels like who they are. But when we start looking at the timeline, there is almost always a period of sustained pressure that kicked things off. A difficult job. A relationship that drained them for years. A childhood where the stress never let up.
For people carrying childhood trauma or complex PTSD, the stress cascade may have been running on overdrive since they were kids. Their baseline was never baseline. It was survival mode, and it became so normal they stopped noticing it.
What Affects How Your Body Handles Stress
Not everyone's stress response works the same way. Genetics play a role in how sensitive your system is. Some people are wired with a more reactive amygdala, which means their alarm goes off louder and more often.
Lifestyle matters too. Regular physical activity helps lower baseline cortisol levels. Poor sleep raises them. Social connection buffers the effects of stress. Isolation amplifies them. And early life experiences shape how your stress system calibrates itself. If you grew up in an environment where you never felt safe, your system may have set its "normal" at a much higher level of activation than someone who grew up in a stable home.
That is not a character flaw. It is biology doing what biology does with the information it was given.
When to Take It Seriously
Stress is part of life. Your body's response to it is not the problem. The problem is when the response never turns off. If you are living with constant tension, disrupted sleep, a short fuse, physical symptoms your doctor cannot fully explain, or a feeling that you are just going through the motions, those are signs that your stress system may be stuck in the "on" position. And the longer it stays there, the harder it becomes to reset without help.
That is where therapy comes in. Not as a last resort, but as a way to give your nervous system the chance to recalibrate. In my practice, approaches like Accelerated Resolution Therapy (ART) and trauma-informed therapy are designed to work with your body's stress response, not just talk about it.
You can reach us at 587-457-7101 or visit pattersoncounselling.ca to learn more about how we work.