How Trauma Can Cause Chronic Sleep Issues such as Insomnia

It's 2 a.m., and you're wide awake — your mind racing, your heart heavy. You've tried everything from evening teas to calming rituals. Still, sleep eludes you.

For the longest time, I understood that stress was behind why many of us can't sleep. What I didn't fully grasp was just how deeply old trauma—both big and small—can linger and disrupt sleep. It's insidious, creeping into the night and causing chronic sleep issues long after the events themselves.

Trauma is often associated with flashbacks and emotional distress, but the truth is that it also rewires our physical body. From hormone imbalances to hyperawareness, understanding how trauma connects to sleep is the first step toward finding rest again.  

How Trauma Affects the Body  

If you've experienced trauma, you may know the term "fight-or-flight." It's our body's survival mechanism, kicking in when faced with danger or stress. Here is an article to learn more: “I Can’t Sleep: Your Nervous System Affects Your Sleep, A Key to Tackling Insomnia”.

But what happens when your body is stuck in that state?  

Trauma is defined as:

• "big T" traumas: a significant life event, like abuse or combat

• "small t" traumas: ongoing smaller stressors, like childhood neglect or a toxic work environment

Both of these types of traumas can cause chronic dysregulation of your stress hormones — especially cortisol.  Cortisol, often called the "stress hormone," spikes when we're alarmed. Typically, cortisol dips as the danger passes.

However, for those with unprocessed trauma, cortisol can stay elevated for long periods, throwing your body's natural rhythms off balance. When your cortisol levels are high at night, it's as if your body is on "high alert," preventing you from entering the calm, restorative state needed for sleep.

Childhood Trauma and Its Long-term Effects on Health and Sleep

The book Childhood Disrupted by Donna Jackson Nakazawa opened my eyes to how childhood traumas carry forward into adulthood, sometimes in ways we don't recognize immediately.

Nakazawa dives into the Adverse Childhood Experiences (ACEs) study, showing how early life trauma changes our biology, increasing risks for mental health struggles, chronic illnesses, and yes, sleep disorders.  Here is the questionnaire to see how these ACEs apply to you.

One quote from Nakazawa that stuck deeply is: "Our biography becomes our biology." That explanation helped me understand why my racing mind at 2 a.m. wasn't just "overthinking." Trauma from years ago had reprogrammed how my brain and body respond to stress, even in seemingly quiet moments.  

For those of us with unresolved childhood trauma, our nervous system becomes over-sensitized. A comment from a partner or co-worker spins in our brain repeatedly, noises seem louder at night, the quiet feels unsettling, and the brain—built to protect us—works overtime scanning for threats.

This hypervigilance is exhausting, and yet, it can make desperately needed sleep all but impossible.  

What's even more striking is how significant childhood trauma impacts cortisol levels. People who've experienced trauma as kids often have higher and more reactive cortisol levels as adults, leaving their bodies in a constant state of alert.

Nakazawa also explains how trauma leads to increased "neuron clippings" during childhood brain development, leaving less neural material to work with as adults. These biological changes help explain why the effects of early trauma can feel so deeply rooted and difficult to overcome, influencing everything from sleep to emotional regulation.

The Role of "Small t" Trauma in Sleep Disruption  

When we talk about trauma, many people dismiss their experiences if they don't fit into the "big T" categories like serious accidents or abuse.

But small, repetitive stressors have a sneaky way of piling up, too. Daily micro-aggressions, feelings of being unsafe at work, or growing up in an environment where you haven't emotionally supported all count as small t traumas — and they, too, create chaos in your body.  

Dr. Bessel van der Kolk, acclaimed author of The Body Keeps the Score, explains it well. He writes, "Trauma results in a fundamental reorganization of the way mind and brain manage perceptions. It changes not only how we think but also our very capacity to think."  

Essentially, your nervous system becomes overly reactive to what it perceives as threats, whether they're real or imagined, big or small. This can lead to nightmares, difficulty staying asleep, or waking up feeling unrested even after a seemingly whole night of sleep.

There's a saying that describes small t traumas as "death by a thousand paper cuts." Individually, they might not seem like much, but over time, those wounds create deep-rooted patterns of stress that, like a quiet thief, steal your peace of mind — and your sleep.  

Why Imbalanced Cortisol Levels and Sleep Don't Mix  

When it comes to chronic Insomnia tied to trauma, cortisol stands out. Elevated cortisol at night keeps your body in "go" mode when it should be signaling rest. This leads to what researchers call a "hyper-aroused state," where you might feel:  

• Restless and fidgety in bed.  

• Mentally "awake" even though you're physically drained.  

• Hyper-focused on small sounds or sensations in your environment.  

• Difficulty falling asleep despite feeling tired.  

• Waking up frequently throughout the night.  

• Racing thoughts that make it hard to relax.  

• Feeling tense or unable to "shut off" your mind.  

• Increased irritability or frustration due to lack of sleep.  

• Sensitivity to light or noise, making it harder to settle.  

• Waking up feeling unrefreshed or still exhausted.  

I've personally experienced this—lying there, unable to shake the feeling that I'd forgotten something or needed to "resolve something urgently," even though no such thing existed.  

Dr. Matthew Walker, sleep expert and author of Why We Sleep, explains, "Elevated cortisol is the antithesis of healthy sleep. It prevents the body from calming down, disrupting the natural progression into sleep's deep, restorative stages."  

Cortisol wakes up other hormones, too, like adrenaline, which worsens the problem. Where we'd generally transition to deep sleep stages that repair the body and mind, elevated cortisol pulls the brakes, locking us into lighter, more fragile sleep. Over time, this contributes to chronic fatigue, brain fog, anxiety, and physical strain.

Read more about cortisol and sleep healing here.

Finding Hope and Healing  

If you're reading this and feeling seen but unsure what to do, you're not alone—and don't lose hope. Chronic sleep issues caused by trauma don't resolve overnight (pun intended), but healing is possible. Here's what I've found helpful in my own experience and research:  

1. Breathwork and Meditation  

Trauma keeps the nervous system stuck on high alert. Breathwork and meditation can help calm the body and retrain the system to feel safe again. Apps like Insight Timer, Calm, or Headspace are tools to help you feel less stressed and more resourced. Here is an article I wrote about how to use Guided Meditations for Sleep.

2. Acupuncture  

Acupuncture is a powerful tool for regulating the nervous system and improving sleep quality. We use thin acupuncture needles to insert in strategic places to release stress and long-term tension. See a more in depth article about acupuncture here.

3. Functional Medicine Testing for Root Cause Healing  

Sometimes, chronic sleep issues are tied to underlying imbalances or deficiencies. Functional medicine testing can uncover root causes, such as hormone imbalances, nutritional deficiencies, or chronic inflammation, providing targeted solutions to support long-term healing.  

4. EMDR or Similar Therapies  

Eye Movement Desensitization and Reprocessing (EMDR) and similar therapies process unresolved trauma, especially when you can't even remember certain events. These approaches help rewire how the brain responds to past painful experiences.

5. Move Your Body Daily  

Regular movement, whether walking, doing yoga, or engaging in more intense exercise, helps reduce stress and increase happiness.

6. Surround Yourself with Supportive People  

Healing is more effortless when surrounded by people who understand you, show kindness, and support your journey. In a nurturing environment, you can heal faster and nurture your healing process.

7. Rethink Your Wind-Down Routine  

Your evening routine might need some extra attention. Create a longer or more mindful process to help you relax fully before bed. Small rituals like reading, journaling, or warm bathing can significantly impact.  

8. Eat Protein Three Times a Day  

Maintaining steady blood sugar levels is key to regulating your nervous system because eating protein with every meal can help prevent blood sugar dips that might aggravate cortisol spikes, keeping your body and mind balanced throughout the day.  

9. Set Boundaries  

If certain situations, people, or environments trigger your nervous system to go into hyperarousal, setting boundaries is essential. Protect your energy and create safe spaces to minimize unnecessary stress.  

You can sleep well again

Understanding how trauma causes chronic sleep issues has completely shifted how I view the relationship with rest. Learning about the role of high cortisol, hypervigilance, and the long shadow of unprocessed experiences has helped me support many patients gradually getting better.

If you've been wrestling with sleepless nights, remember this—your struggles are valid, but they don't have to be permanent.

Reach out, I can help

If you are curious how I could support you, schedule a free consult for local help in Boulder, CO, or long-distance via telehealth.

Also, check out my book, The Deep Blue Sleep—A Roadmap to Fall Asleep and Stay Asleep Naturally. This book provides a comprehensive guide to understanding the nervous system's role in sleep, strategies for improving sleep, and tips for reducing anxiety related to Insomnia.

Available in Paperback, E-book, and Audiobook.