Concussion + Mold = Double Whammy
Recovering from two things that a lot of people know very little about
I’ve been traveling continuously for 10 months, with only a single suitcase and a computer bag for my things (if you want to read about my travel adventures, I have a separate substack called You’re a Trip).
One of the things I brought with me and use almost daily is a Vielight device (the Neuro Gamma).
This week, I watched a video with NHL player Tim Thomas talking about his use of the same device (albeit a newer model). You can watch it here or below.
Something that comes up—very briefly—in this video is mold. He said he wasn’t able to see progress until he removed himself from chronic mold exposure.
Since there wasn’t much follow-up on that, I thought I’d devote a bit of time to it here—with the usual caveat that I am not a doctor or a medical professional of any kind—see full disclaimer below.
TBI and Mold Symptoms: A Venn Diagram
Like Tim Thomas and many thousands of people around the world, I didn’t know I was living in a moldy house—there is unfortunately very little public awareness about mold.
And I had no idea how much overlap there is between post-concussion syndrome (PCS) and mold illness. In a Venn Diagram, the following symptoms would be shared in the space between the two.
Shared Symptoms Between TBI and Mold Illness
Headaches: Both conditions commonly cause headaches. PCS headaches often feel like migraines or tension-type headaches, while mold exposure can also trigger headaches ranging from mild to severe.
Dizziness: This is reported in about half of people with PCS and is also a symptom of mold exposure.
Fatigue: Fatigue is a common symptom in both conditions.
Cognitive issues: Both conditions can cause problems with concentration and memory. Brain fog!
Irritability: This psychological symptom appears in both PCS and mold-related conditions.
Light and noise sensitivity: Sensitivity to light and noise occurs in both conditions.
Nausea: Both PCS and mold exposure can cause feelings of nausea.
TBI and Post-Concussion Syndrome Specific Symptoms
Symptoms that would appear only in the PCS circle of the diagram include:
Depression and anxiety (more prevalent in PCS)
Sleep disturbances (insomnia or sleeping too much)
Ringing in the ears (tinnitus)
Blurry or double vision
Neck pain
Personality changes
Restlessness and mood swings
Mold Illness Specific Symptoms
Symptoms that would appear only in the mold illness circle of the diagram include:
Respiratory symptoms (coughing, wheezing, difficulty breathing)
Nasal and sinus congestion
Eye irritation (itchy, red, watery eyes)
Throat irritation
Skin irritation and rashes
Sneezing and runny nose
Postnasal drip
Pain syndromes (joint and muscle aches)
Movement disorders (in severe cases)
Seizures (in severe cases)
Both TBI and Mold independently lead to Leaky Gut and Leaky Brain—by different mechanisms
A TBI (or repeated sub-concussive blows to the head without ever being knocked unconscious) can directly and indirectly damage the blood-brain barrier (BBB). Things that wouldn’t normally make it past the BBB can then waltz right in—causing chronic inflammation and other issues.
Both TBI and mold illness can independently contribute to leaky gut and leaky brain (blood-brain barrier dysfunction), though it happens through distinct mechanisms with each.
Here’s the breakdown:
How TBI leads to Leaky Gut
Traumatic brain injury (TBI) triggers gut inflammation and intestinal permeability (leaky gut) within hours to days. (Very specific probiotics have been shown to mitigate intestinal permeability and BBB dysfunction when taken after a TBI in clinical settings.)
Brain inflammation disrupts gut-brain communication, altering gut motility and immune responses.
TBI reduces gut mucus production and weakens tight junctions between intestinal cells, allowing toxins and undigested particles into the bloodstream.
Symptoms: Nausea, bloating, diarrhea, and constipation are common.
How Mold Illness leads to Leaky Gut
Mycotoxins (mold toxins) directly damage the gut lining by reducing mucus and breaking down epithelial tight junctions.:
Mycotoxins trigger gut inflammation and dysregulate immune responses, worsening conditions like IBS or leaky gut.
Chronic exposure weakens gut defenses, increasing susceptibility to infections.
How TBI leads to Leaky Brain (Blood-Brain Barrier Dysfunction)
Concussions (or blows to the head without loss of consciousness) directly disrupt the blood-brain barrier (BBB), allowing serum proteins and inflammatory molecules into the brain.
Swine models show BBB leakage (fibrinogen, IgG) and diffuse axonal injury post-concussion.
Human studies link BBB dysfunction to prolonged cognitive impairment and neurodegeneration.
How Mold Illness leads to Leaky Brain (Blood-Brain Barrier Dysfunction)
Mycotoxins like beauvericin and enniatin cross the BBB due to their fat solubility, accumulating in brain tissue.
Oxidative stress from mycotoxins damages brain lipids (lipid peroxidation), worsening neuroinflammation.
Mold exposure correlates with EEG abnormalities and frontal cortex dysfunction in humans.
The implications of the double whammy—and new questions
With each of these conditions being devastating, how much more devastating are they when they overlap? And how much more difficult to determine the root causes of symptoms.
Suffering from both conditions at the same time could be especially challenging and, as with Tim Thomas, one may not see any progress until the exposure to mold ceases.
One big implication is that TBIs can lower the barriers that let mold into the body and brain—if one is already living in a moldy house, a TBI could make one’s exposure to mold suddenly far worse.
Conversely, if one is chronically exposed to mold, and one’s gut and brain barriers are therefore compromised, one might then be at greater risk of developing long-term PCS after a TBI.
I’m guessing that many people (like me in the past) unwittingly sit in houses breathing invisible mold spores and mycotoxins every day, wondering why they can’t get better after a TBI—not knowing that a subset of their lingering symptoms might be caused by hidden mold exposure.
With mold, it’s important to know there are genetic differences that can make a person better at tolerating mold exposure. Some people are simply better at clearing toxins than others.
What happens to such people when they have a TBI? Living in a moldy house (which is very easy to do unwittingly) may have appeared to be unproblematic on the surface, but after a TBI the same house could make a complete recovery impossible. And this might confuse our inner scientist who thinks that if something wasn’t a problem before, it shouldn’t be a problem now. But the lowering of our internal barriers might have changed everything.
Is there a hidden epidemic of people suffering from both PCS and mold illness who can’t break the vicious cycle? Or do many people unwittingly suffer from mold illness after recovering from a TBI, thinking their issues are long-term PCS?
The Good News: Unlike Post-Concussion Syndrome, Mold Illness is Relatively Easy to Diagnose
Syndromes are a collection of common symptoms, they are not concrete things (such as cancer or crabs). A concrete thing is easier to treat—if it’s treatable. A syndrome like Post-Concussion Syndrome often provokes a big shrug of the shoulders—few know where to begin or what to do.
Mold is concrete. It’s easier to diagnose, which means it’s easier to rule out.
There are quality tests one can take (usually a urine-based test done after performing certain protocols) that reveal whether or not one has a mold illness. If these quality test results are clear, you’re in the clear, and you can attend to other things.
To find mold-literate doctors, one can use this Find a Practitioner tool.
It doesn’t take much mold to make a person chronically ill. Mold colonies, even just a few square inches in size, can produce and release millions of microscopic spores into the air.
You might have mold in your house if:
There was ever a single water-intrusion anywhere in your house (yep, that applies to a lot of houses). An internal leak. A roof leak. A bathtub overflow. A flood.
You have a forced-air heating system that wasn’t routinely cleaned and inspected—these systems can easily send mold spores to every room in a house.
There is any hint of an odd smell in any space in the house, including closets, basements, and attics. But if there are no odd smells, that doesn’t mean a house is in the clear.
You live in a wood-framed house that’s been around for a while and maybe wasn’t maintained very well for decades.
The original uncarpeted wood or concrete floors have been carpeted over.
Closets were used to store rain-soaked jackets.
You bought used furniture that was filled with mold spores, unwittingly colonizing your own house with mold.
And on an on
One can get comprehensive mold testing of a residence by a trained and skilled professional who can find mold in all the places it hides. Air samples and swab samples should be done.
My understanding is that it’s best to have the testing and remediation done by different people. It’s also best to hire your own tester of you are a tenant because the tester that a landlord hires has the wrong incentives.
The remediation itself can be very tricky business—it’s not handyman work or DIY. As with any category of business, only a small percentage of mold remediation firms are excellent.
If mold has colonized your body, it can be a real bear to remove and recover from, because mold is alive and it fights back. Part of the process involves eventual gut barrier and BBB repair (but other steps are needed first).
Setting aside mold, repairing the brain and gut barriers is a known, concrete process. I’ve gone through that process with the guidance of an ND for PCS (before knowing that I was chronically exposed to mold).
Did I inadvertently help myself recover from mold by doing a gut repair protocol? Probably. I won’t know until I’ve done the testing and re-testing that will tell me definitively.
Did the Vielight, which I used for Post-Concussion Syndrome, inadvertently help me recover from mold illness or at least mitigate it? Maybe.
Life is often about asking the right questions. Hopefully I’ve asked some good questions here. I don’t necessarily have the answers—again, I am not a doctor or medical practitioner of any kind. I am a patient and these are the questions I’ve discovered on my journey.
Brainwave is a newsletter about brain health, a personal blog about my own journey, and an informational resource for people whose symptoms haven’t resolved after a concussion or mTBI. I aim to present this information clearly and concisely, spelling out what’s backed by science and what remains unknown. Nothing here is meant as a substitute for professional medical advice, diagnosis, or treatment. I am not a physician or a healthcare practitioner of any kind; I’ve had a lot of sports-related head trauma and had to learn this stuff the hard way. If you found this information helpful or know someone who might benefit from it, please share and subscribe to Brainwave.
Great article!