From Psychology to Mitochondria
Understanding stress from the inside out
Every so often, I read a paper that completely shifts how I think—and I find that incredibly exciting. I love learning new ways to improve wellbeing and performance, especially in a world that’s fast-paced, demanding, and constantly changing.
What I didn’t expect was to find myself diving into the cellular level of stress—yet that’s exactly what happened. Understanding how mitochondria function has transformed the way I view the body’s ability to adapt to stress, recover from adversity, and maintain resilience.
In fact, it’s strengthened my belief in interventions like Altitude Training, which is known for one of its most powerful effects: replenishing and supporting mitochondrial health.
Coming Up Next
Below, I’ll outline some key insights from the paper that inspired this post. My hope is that you’ll come to see your mitochondria as an ally in stress recovery and resilience and mental health.
I’m not a medic or biological scientist, so I encourage you to read the research for yourself if you’re curious. But understanding even the basics of how our cells generate energy can deepen how we approach wellbeing.
Mitochondria: The Powerhouses Behind Stress Resilience
To handle stress and maintain high performance, the body needs one essential ingredient: energy.
At the cellular level, that energy comes primarily from mitochondria—tiny organelles found in virtually every one of our trillions of cells. Their job? To convert the oxygen we breathe into usable energy that powers everything from healing and growth to cognitive function and emotional regulation.
In fact, mitochondria generate over 90% of the body’s energy, in the form of adenosine triphosphate (ATP)—the molecule that fuels every biological process.
The biggest energy consumers in the body are the brain, muscles, liver, kidneys, heart, lungs, and digestive system—all systems that work hard to keep us alive, responsive, and adaptable to an ever-changing world.
But energy production is just the tip of the iceberg when it comes to Mitochondria. Mitochondrial function underpins almost all metabolic processes, as the image opposite demonstrates.
Why Mitochondria Matter for Stress Resilience
When it comes to handling stress, mitochondria do far more than just produce energy. These tiny organelles fuel the entire mind-body system, powering everything from physical performance to psychological adaptability.
Here’s what mitochondria are involved in:
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Producing ATP, the body’s main energy currency
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Regulating the stress response via interactions with the neuroendocrine and metabolic systems
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Metabolising steroid hormones involved in inflammation and immunity
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Supporting brain function, emotional regulation, and even social behaviour
When mitochondrial function is disrupted under experimental conditions, we see clear changes in how the body and brain respond to stress—physiologically and behaviourally. There’s also growing evidence that mitochondrial health affects conditions like depression, anxiety, ASD, and ADHD.
By the way, its worth mentioning that many of the clients I work with don’t necessarily think of themselves as lacking energy. I find that many people who live in near constant fight / flight reactions are finding energy fulled by stress chemicals and an inability to be at rest. It’s only later as their bodies return to parasympathetic balance that they can look back and see that the way they have been living has been exhausting and that they were at times running on empty.
Why Wasn’t I Taught This in Psychology Training?
In all my years of psychological education, mitochondria were never mentioned. I was never encouraged to consider where the energetic capacity for stress adaptation comes from.
Learning now that our ability to manage stress—mentally and physically—depends on the energetic resources within our cells is not just fascinating… it also makes perfect sense. I’ve met so many people who have struggled for years with adversity and struggle so it’s obvious that this will have both and energetic source and consequence.
It adds another vital lens through which to support clients’ recovery, resilience, and wellbeing.
What Is Stress, Really?
At its core, stress is anything—real or imagined—that requires the brain and body to adapt in order to maintain homeostasis (internal balance). And adaptation takes energy.
While all biological functions require energy, the stress response demands more than the basics. It’s an energy-intensive, whole-system event—meaning that stress management is deeply linked to our cellular energy capacity and how it can support our body to adapt.
Types of Stress: From Helpful to Harmful
Not all stress is bad. In fact, some stress is essential for growth. But the body’s response—and the long-term effects—depend on the type of stress and how well we can recover.
1. Good Stress
This is the kind that challenges us in a positive way: public speaking, job interviews, intense workouts. Stress hormones like cortisol and adrenaline are activated when needed, then switch off once the challenge ends. Recovery happens naturally.
2. Tolerable Stress
This includes significant life events—loss, breakups, grief—but where we have enough internal resources and external support to recover.
Stress mediators may remain elevated for a while, and if the system is overwhelmed, can begin to cause metabolic, immune, and emotional dysregulation (McEwen, 1998). But with time and support, we return to balance.
3. Toxic Stress
This is when adversity strikes, but support and internal resilience are lacking.
The person feels overwhelmed and out of control, stress mediators remain active for too long, and the body enters a state of chronic dysregulation—leading to allostatic load (Cohen et al., 2007). Over time, this contributes to both mental and physical illness.
What Is Allostatic Load (and Overload)?
“Allostasis” refers to the body’s ability to maintain stability through changing circumstances. But when the systems designed to help us adapt to stress (neuroendocrine, metabolic, immune) become overused or dysregulated, we develop what’s known as allostatic load.
If these systems are pushed too far for too long, we move into allostatic overload. Symptoms include:
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Chronic inflammation
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Hormonal imbalance
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High or low cortisol
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Fatigue and burnout
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Anxiety, dissociation, depression
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Physical health issues
These outcomes are not just psychologically triggered —they’re signs of depleted biological resilience.
Stress, Eating, and Energy-Seeking Behaviour
Stress doesn’t just change how we feel. It also changes how we eat and store energy.
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Stress increases cravings for high-calorie “comfort” foods (Masih et al., 2017)
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It reduces fat oxidation and increases insulin production (Kiecolt-Glaser et al., 2015)
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It shifts fat storage to visceral (belly) fat, which is more metabolically active
This isn’t just about emotional eating. These are body-driven responses aimed at replenishing energy and restoring balance.
It’s fascinating to rethink stress eating not as self-sabotage, but as an innate biological strategy to maintain survival.
Mitochondrial Dysfunction and Stress Sensitivity
A groundbreaking paper by Picard and McEwen (2018) demonstrated that psychological stress alters mitochondrial function and changes how the entire body reacts to stress. Different types of mitochondrial impairment produced unique stress response “signatures” across systems.
This helps explain how mitochondrial dysfunction is linked to:
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Inflammation
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Hormonal imbalance
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Mood disorders
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Metabolic issues
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Reduced adaptability to stress
In short: mitochondria are a key player in translating stress into illness.
The Energy-Stress Link in Mental Health
Even without physical threats, chronic psychological stress can:
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Dysregulate metabolism
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Raise cortisol and blood sugar
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Promote insulin resistance and fat storage
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Reduce physical activity and mood (Karatsoreos et al., 2010)
This energy-metabolism-emotion loop gives us a whole new way to understand depression, anxiety, overwhelm and burnout. It also accounts for many of the strategies we use to cope with stress based on energy depletion.
Final Thoughts: Body or Mind First?
We’re often told that stress is all about mindset.
“Think positive. Reframe the situation. Breathe through it. Improve your coping strategies.”
But this emerging research suggests that our physiological resources and energy capacity—especially at the mitochondrial level—play a massive role in how well we adapt to the challenges we face. Without our bodies being able to support our helpful coping and adaptability, we may succumb to coping based on an attempt at energy renewal – outside of our conscious control. It also highlights that our stress responses, when overused and overloaded may contribute to translating stressful experiences into physical and psychological illness (Picard et al., 2014).
So maybe it’s not about mind over matter. Maybe mind is matter—the state of our phsysiology is reflected in our psychology.
Based on the paper:
An energetic view of stress: Focus on mitochondria
Martin Picard, Bruce S McEwen d , Elissa S Epel e , and Carmen Sandi
Front Neuroendocrinol. 2018 Apr; 49: 72–85.
Published online 2018 Jan 12. doi: 10.1016/j.yfrne.2018.01.001