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Mycotoxins & Neurotoxicity Series

Mycotoxins and Neurotoxicity Part 1: Brain Fog

January 31, 2023

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Part 1

Part 2

Part 3

Part 4

Explore The Series

Part 1

Part 2

Part 3

Part 4

What Exactly is Brain Fog?

When it comes to mold symptoms, brain fog is a symptom and term used often by both patients and doctors loosely.  Each time I ask mold sensitive individuals to describe it I receive similar but distinctly different answers. Exploring clarity for description purposes is worth investigating.  I searched medical dictionaries and publications for a consensus understanding with limited success and more questions than answers. There was one vague definition in Merriam-Webster Dictionary describing it as “a usually temporary state of mental capacity marked by inability to concentrate or to think or reason clearly.” Several medical dictionaries did not provide answers; nor did they provide clear descriptions. In addition, the Diagnostic and Statistical Manual of Mental Disorders (DSM) used by psychiatrists does not have Brain Fog as recognized medical condition. It turned out that Wikipedia (Not a standard source for official definition) provided the clearest definition that is commonly agreed upon by Doctors and Patients.  Brain fog is “a condition that affects all ages and which is characterized by confusion, decreased clarity of thought, and forgetfulness.  It is not regarded as a real condition.” Through the next few articles, I will describe “Brain Fog”, mycotoxin neurotoxicity, and causes with patient specifics and examples.  

Our Purpose: These articles are researched and written to provide helpful information to anyone with a debilitating chronic illness. In most traditional medical practices, mold falls in a blind spot.

    • Mold can cause severe illness or death, caused by toxins, biological and chemical pollutants.
    • Today’s healthcare system processes are not designed or equipped to diagnose and treat environmental illness.
    • Recent awareness of environmental illness has been magnified due to the severity of Covid pandemic.
    • There are thousands of molecules, derived from chemicals or microbes, that are poorly understood, untested, or unrecgonized.

Symptoms and Fear

In addition to searching the literature for better descriptions, I reached out to physicians who treat environmental illness and mold patients that have experienced “Brain Fog”.  While brain fog is not a medically recognized term, it is commonly used to describe feelings of confusion, forgetfulness, inability to focus, difficulty comprehending, and lack of mental clarity. These disruptions in thinking can divert any action or conversation significantly, especially in a professional capacity. Brain Imaging It is important to note that neurological and cognitive symptoms suffered are often the “scariest” for patients. This remains true, regardless of the magnitude of the impact on their daily functions. Unfortunately, the fear has been described as a “genuine concern that the symptoms are those of onset dementia, or neurodegenerative disease”.  In older patients above 50, thoughts suggesting the beginnings of Dementia or Alzheimer’s are horrifying.

Here are some descriptions provided to me by patients:

  • “Foggy”, describing feeling unfocused, “I just can’t think!” or “an inability to function normally.”  One patient who home schooled her children described her inability to teach her kids coupled with the guilt of falling behind in their curriculums.
  • “Momentarily forgetting basic facts about myself, my life, or the world around me.” Forgetting names or favorite memories (movies, actors names, etc.) that you normally would never forget.
  • “Forgetting what you’re doing while you are doing it.”  Here the patient described driving somewhere they normally go and not remembering how to get back.
  • “Placing items in different places than normal and not being able to find them.’’
  • “Forgetting how to operate an appliance you use every day.”
  • “Forgetting commonly used words.”  One physician described to me that he forgot the word shoe when talking to a patient while suffering from brain fog.
  • “Using words in the wrong order.”
  • “Forgetting how to spell familiar words to the degree that I have to look them up and still cannot spell them, resulting in a ‘research project’.”

Brain fog can also create or accompany physical symptoms.  These include:

  • Low energy or fatigue
  • Irritability
  • Headaches/Migraines
  • Low motivation
  • Depression or anxiety
  • Trouble sleeping
  • Difficulty exercising, dancing, or playing 

Medical Causes

For mold patients, I have described some of the unexplained symptoms of toxic mold exposure  in my earlier article: “7 Medical Consequences and 4 Unique Hardships Endured by Mold Sensitive Patients.”  But brain fog is also described in a variety of chronic medical conditions. Many of these illnesses are well defined, while some are not. Well understood causes of brain fog include chemotherapy (“Chemo Brain”), brain injuries, heavy metal toxicity, multiple sclerosis, neurodegenerative disorders, side effects from some medications, and others.  There are also recognized disease diagnoses that have limited or unknown causes such as Fibromyalgia, Silent Celiac Disease, Chronic Fatigue Syndrome, etc.. Brain fog is commonly a symptom of these diagnoses.

Common Catch-all diagnosis

Chronic Fungal Sinusitis Can Cause Brain Fog in a Variety of Ways:

  • When the nose is congested, breathing through the mouth results in a lower oxygen intake.
  • The sinuses are an ideal environment for molds to reproduce.  When that occurs, a large, visible fungal ball can be found in the sinuses.
  • Side effects from some medications used to treat Sinusitis
  • Poor Sleep
  • Inflammation 
  • Migraines and Sinus Headaches

It turns out that inflammation (caused by the inflammatory response to mold) often causes brain fog as a symptom.  There are too many related autoimmune diseases to name.  Some diagnosable inflammatory diseases include (Rheumatoid Arthritis, Crohn’s Disease, MS, etc..) where brain fog is sometimes described as a symptom. For mold sufferers, what is most relevant is that brain fog can be caused by a variety of inflammatory, toxic, and allergic responses to inflammation. Infections resulting from mold exposure can create imbalances with hormones, neurotransmitters, and nutrition.  Chronic sinusitis is often cyclical where patients suffer from alternating infections of the sinuses created by a common practice of using antibiotics universally to treat sinus infections.

Chronic Sinusitis Sufferer's Lifecycle

You can learn more about “What Makes Chronic Sinusitis Chronic” HERE.

Environmental Causes of Brain Fog

We encounter environmental factors that we may have some control of throughout our days, which may be contributing to Brain Fog.  Paying attention to these factors can help us modify our lifestyles and behaviors to improve our wellness and eliminate brain fog.

Potential Causes of Brain Fog

Contributing Factors


Allergies Indoor and outdoor allergens, food Allergies, especially gluten, can contribute to brain fog. Higher levels of of inflammatory molecules including histamine and leukotrienes can stimulate microglia activation.
Candida/fungal Overgrowth/Infection Candida Albicans are fungi found in most people’s microbiome. A diet high in sugars, alcohol, and refined carbohydrates can cause candida overgrowth or candidiasis. Common symptoms include chronic fatigue, gastrointestinal issues, mood disorders, “stoned or drunk” feelings. Infections: such as vaginal yeast infections, thrush, toenail fungus, and sinus infections are common. The body must also remove candida toxins emitted such as aldehyde and alcohols.
Dehydration as a Result of the Environment 75% of Americans do not drink enough water. The brain is 75% water . It takes only 2% dehydration to affect clear thinking. 90 minutes of sweating can shrink the brain as much as 1 year of aging. Hydration is critical to wellness.
Diet as a Result of the Environment Sugar, refined carbohydrate, inadequate fat intake, food additives: MSG, aspartame, sucralose, alcohol, gluten, caffeine, caffeine withdrawal are common contributors. Foods that cause inflammation: sugar, high fructose corn syrup, and simple carbohydrates that feed mold overgrowth within the microbiome and chronically increase insulin levels can impact metabolism.
Lack of Quality Sleep as a Result of the Environment 40 M Americans suffer from 70 different sleep disorders. Sleep is essential to how the brain works. During sleep is when your glymphatic system and cerebral spinal fluid flushes and detoxifies the brain. Adrenal, thyroid, cortisol, and estrogen imbalances can reek
Stress as a Result of the Environment Lifestyle, Stress hormones Adrenal, thyroid, cortisol, and estrogen imbalances can reek havoc on wellness..
Pollutants Toxic gases, particulate matter, chemicals, biological molecules, etc., that modify the natural characteristics of the Earth’s atmosphere. Some common sources of air pollution include wildfires, volcanic eruptions, burning of fossil fuels, mining operations, household combustion devices, motor vehicles, and exhaust gases from industrial facilities
Environmental Toxins Heavy metals, VOCs, Mold Mycotoxins are common Medical attention is often required to optimize metabolism. Proper detoxification by the body’s organ systems is time consuming and necessary.


About Brain Fog

Brain Fog is a symptom that is always taken seriously by patients because it can create fear about dementia or other neurological diseases. It also makes people dysfunctional compared to their normal condition.  A less traveled path that may be more productive is to see a physician, integrative or functional physician, or Naturopathic Doctor that treats environmental illness.  These healthcare professionals take more time with patients (often 45 min to 1 hour) to listen closely to patient symptoms.  They often ask probing questions about their medical history and environment that can lead to identifying the cause of the brain fog.  This can help mitigate factors that cause the brain fog without medication that can mask some symptoms or create new symptoms. Avoiding the frustrating path of seeing a series of doctors and taking medications can help patients avoid what can be years of suffering until the cause is addressed. In addition, if your environment is the cause, medication is unlikely to be totally effective if you are returning to the cause or behavior that is causing these symptoms.

What Can Be Done For Mold and Chronic Sinusitis Sufferers:

  • Test your home for mold using the comprehensive and easy-to use Immunolytics Mold Test Kit.  You can purchase mold test plates and absorbent swabs to obtain comprehensive lab reports and helpful explanations on your mold problem.
  • Agrumax Dietary Supplement added to daily nasal washes, and/or ingested by mixing into in a glass of water, may provide the body relief from the continuous inhalation of fungi and address candida or fungal growth in the gut.  
  • Periodically use an antimicrobial fog inside your home to systemically address mold in the entire volume in your home and HVAC unit.  Over filling the air volume with HavenFog Kit ensures that the fog addresses every surface area as well as corners and crevices.
  • Practicing good mold hygiene in your home by using the Haven Mister or cleaning with HavenMist  or Remedy Mold Solution to regularly bring your fungal air counts down dramatically allowing you to rest and sleep in an environment without continuous inhalation of mold.  
  • Washing clothes and especially linens with Remedy Laundry Detergent will remove mold during your wash cycle, eliminating mold tracked into your home and allowing you to sleep soundly without mold in your bed.
  • The addition of HEPA Air Purifier or use of Remedy Air Maintenance Candles where you relax will help remove mold and mycotoxins from your immediate air efficiently.

“Brain Fog” remains a commonly used term by patients and doctors.  Perhaps, these descriptions can help provide a clearer understanding of your symptoms and ways they can be addressed without hopelessness or panic.  The next article will explain that mold mycotoxins are potent neurotoxins that cause brain fog and other neurological disorders.

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