After a brain injury, like a concussion, stroke or TBI, whiplash, the brain goes into a metabolic crisis. This is what the cells are doing to desperately try to restore balance, but their normal fuel system - glucose- becomes impaired. This is called glucose starvation.
Release of Emergency Messengers
Immediately after an injury, neurons release a surge of neurotransmitters to communicate the injury, especially glutamate. This overstimulates cells, causing them to fire excessively and burn through stored energy (ATP).
Glutamate is the primary excitatory neurotransmitter in the brain. It’s the signal your neurons use to “turn on” communication — it excites, activates, and coordinates function. When a brain injury occurs — even a mild one like a concussion — neurons are suddenly stressed, membranes are disrupted, and ionic balance is lost.
Large amounts of glutamate are released for three key reasons:
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In the acute phase, glutamate release serves as a coordinated alarm signal:
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It tells surrounding neurons, glial cells, and even immune cells that injury has occurred.
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It initiates neuroinflammation as part of cleanup and repair.
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It prompts the release of stress hormones (like cortisol and norepinephrine) to stabilize blood pressure and maintain vital function.
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It helps reroute attention and resources — you literally can’t think about anything else when the brain is under threat, which helps protect it from overstimulation.
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In other words, the glutamate surge is how the brain says, “Stop everything — we have to protect and repair.”
Glutamate activates NMDA and AMPA receptors on neurons, allowing calcium and sodium to flow into cells. A controlled version of this is how learning and neuroplasticity occur. But during injury, it becomes excitotoxic — too much calcium overwhelms mitochondria, leading to oxidative stress and cell death. So, glutamate’s surge is both a call for help and a double-edged sword:
It’s necessary for initial communication and survival, but if it stays elevated, it creates secondary damage and deepens the brain’s metabolic crisis.
From the lens of Neurogenesiology™, glutamate is not just a chemical — it’s a safety signal. When the nervous system perceives an emergency, glutamate acts as the language of that alarm. It heightens awareness, vigilance, and cellular activation. But if the body never receives the message that it’s safe again, the glutamate cycle doesn’t calm down — and the system stays stuck in high-alert, over-excited patterns.
That’s when we start to see symptoms like:
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Brain fog
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Light and sound sensitivity
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Anxiety or irritability
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Sleep disturbances
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Chronic fatigue
All are signs that the brain never fully exited its emergency mode.
Healing involves helping the brain transition from excitatory dominance to regenerative signaling again.
That includes:
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Supporting GABA-glutamate balance through nutrition and neurotransmitter therapy.
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Calming the autonomic nervous system so the body perceives safety.
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Nourishing mitochondria so energy production can stabilize.
Blood Flow to the Brain Drops
At the same time, blood flow to the brain drops significantly (called cerebral hypoperfusion). So even though demand skyrockets, the brain isn’t receiving enough oxygen or glucose to meet that demand.
The mitochondria are especially sensitive to trauma and inflammation and if they are impaired they can’t convert glucose into ATP well, so even if glucose is present, they can’t use it. It’s like having food in the kitchen but it’s locked behind glass cabinets you don’t have access to. There’s enough fuel in circulation but without access, the brain is functionally starved.
When glucose use (metabolism) is impaired, the brain might turn to ketones as an alternative fuel source. This is why we rely on protocols that utilize metabolic flexibility - supporting mitochondrial energy and repair, reducing inflammation, and providing ketone based energy sources like fatty acids, until glucose use has normalized.
Blood sugar balance and maintaining that delicate equilibrium becomes high priority. And this is why a person might feel hypervigilant, they may feel brain fog and fatigue, shaky if going too long without food, heart palpitations and shallow breath, weak muscles and more. Of course there are other neurotransmitters at play that lend towards these symptoms as well, but blood sugar imbalance is key inside the survival response.
After a trauma, the body will prioritize safety in case something more happens. Blood vessels get restricted through these neurotransmitter messages from the nervous system, and energy is directed for survival, not recovery. This means the brain gets even less access to glucose while the body works to stabilize basic function like breath and heart rate. If you find yourself in this situation, you can take time for breathwork multiple times throughout the day, practice heartmath to regulate breath and heart rate and assist the body into a parasympathetic (healing) state, and sleep (where breath and heart rate has opportunity to naturally calibrate without your thoughts preventing it.
If you've experienced a concussion, you might like this article as well: https://healthclues.info/blogs/blogs/what-your-brain-needs-right-now?_pos=1&_sid=bf6071849&_ss=r
For an appointment or find out which path is right for you, visit ANMCholistichealth.com.
Amanda Wentland, PhD, MSCN, NMD, CNS is a Naturopathic Practitioner, Clinical Nutritionist, and PhD in the Philosophy of Natural Medicine who specializes in nervous system-driven health conditions. As the founder of Neurogenesiology™, she helps clients understand how trauma, stress, and biochemistry shape their body’s ability to heal. Her work blends functional nutrition, neurogenic retraining, and cellular health to restore safety and balance to the brain and body.