10 Warning Signs of Mold Toxicity

author avatar Dr. Eric Berg 08/31/2023

Mold toxicity occurs if an individual develops health complications after exposure to toxic mold spores.  

Toxic mold can trigger various mold poisoning symptoms and may be the reason for unexplained fatigue, respiratory problems, brain fog, migraines, and weakened immune system function.  

Let’s look deeper at mold-related health issues and learn how to detoxify the body after mold exposure.    

Woman finding a moldy environment

What is mold?

Molds are microscopic fungi typically found on damp or decaying organic matter. All types of mold require moisture to grow, which explains why mold thrives in wet and humid environments.     

Mold can form colonies on wood, cardboard, wallpaper, carpets, drywall, fabric, plants, and foods. By digesting the material it grows on, mold obtains the nutrients and energy it needs to survive.  

Mold proliferates by releasing spores, microscopic reproductive cells that float through the air until they settle on a surface that’s favorable for their growth.  

Molds play an important environmental role and help to decay leaves and organic matter needed for healthy and nutrient-rich soils. However, molds that develop indoors can become a problem. 

Indoor mold is a common issue in buildings with poor ventilation, humid climates, and after water damage. 

Mold exposure can also come from the foods you are eating. Everyday food products such as corn, wheat, grains, coffee, dried fruit, and peanuts are often stored in large silos conducive to mold development.  

Mold close up

Is mold dangerous?

There are more than 100,000 known mold species, and most of them are harmless. However, some molds are toxic and pose serious health hazards for humans, pets, and livestock.   

Toxic molds are a group of mold species that release mycotoxins, harmful substances that serve as a defense mechanism and kill other microorganisms and fungi competing for the same space as the mold. 

According to research published by Prof. Mohammed Zain, microbiologist and mycotoxin expert, “There is sufficient evidence from animal models and human epidemiological data to conclude that mycotoxins pose an important danger to human health, albeit one that is hard to pin down.”

Mycotoxins can have toxic effects on the body when inhaled, ingested, or exposed to the skin. Different molds release different mycotoxins associated with various physical problems, including liver damage, reproductive issues, neurotoxicity, and impaired immune functions.  

Here are the five most toxic types of mold:

  • Stachybotrys chartarum, also known as black mold

  • Aspergillus 

  • Penicillium 

  • Fusarium 

  • Cladosporium  

Mold on stored corn

Ten signs of mold toxicity

While mold toxicity is notoriously hard to diagnose, some common warning signs can indicate an accumulation of harmful mold spores in the body.  

Here are ten signs of potential mold toxicity.

1. Allergic reactions 

According to research published in the Journal of Occupational and Environmental Medicine, around five percent of the population is allergic to one or more mold species.

Mold spores and mycotoxins can trigger mold allergies, and symptoms typically develop rapidly after mold exposure. Nasal congestion, wheezing, hives, and coughing are common symptoms of mold-related allergies.  

People with weak immune systems appear at particular risk of developing mold allergies and are advised to limit mold exposure as much as possible. 

2. Unexplained fatigue

Unexplained fatigue is among the most common warning signs of black mold toxicity. 

Mycotoxins released by Stachybotrys chartarum have been found to impair mitochondrial function, which is crucial to generate adenosine triphosphate (ADP), an organic compound that provides the energy needed to support all biochemical processes.   

In addition, mold exposure can activate immune defenses and trigger complex biochemical pathways that enable immune cells to recognize and destroy potentially toxic pathogens. These processes require a significant amount of energy, which can contribute to fatigue and malaise. 

3. Respiratory problems 

Mold exposure can lead to respiratory problems, particularly in individuals who are sensitive or allergic to mold. 

Mold spores can reach all parts of the respiratory tract, including the nose, throat, sinuses, bronchial tubes, and lungs, where they can cause immune responses and inflammation.

Respiratory issues such as sneezing, congestion, chest tightness, shortness of breath, coughing, and wheezing are common mold toxicity-related symptoms. 

Interestingly, research published in European Respiratory Review suggests that environmental mold exposure during childhood can significantly increase the risk of developing asthma and other chronic respiratory conditions. 

Knee pain

4. Stiffness and joint pain

Mold toxins can trigger joint stiffness and cause fungal arthritis, a common warning sign of chronic exposure to Aspergillus or Candida, a widespread yeast species. 

Fungal or yeast spores can accumulate in joints, bones, and surrounding tissues, triggering inflammation and fluid accumulation. This explains why mold exposure can cause musculoskeletal issues such as joint pain and swelling, limited range of motion, and stiffness. 

While fungal arthritis can affect any joint, the knee, hip, ankle, and shoulder joints seem most affected by mold.

5. Cognitive problems

Certain mycotoxins have been found to enter the brain and other parts of the central nervous system, which is linked to neuroinflammation and impaired cognition. 

Mycotoxins are believed to directly damage neurons and interfere with neurotransmitter function, which disrupts the communication between brain cells and leads to cognitive issues such as memory loss, lack of concentration, and brain fog.  

6. Skin irritation 

When the skin comes into contact with mold spores or their byproducts, it can trigger immune responses and cause the release of histamine, a natural compound that triggers inflammation and regulates immune system processes.

Histamine causes increased blood flow, fluid accumulation, and the influx of pro-inflammatory molecules to the site of mold exposure, which typically manifest in symptoms such as itching, redness, and eczema-like rashes.

Mold spores that are ingested or inhaled can cause elevated concentrations of inflammatory compounds throughout the body, linked to health issues, including skin conditions such as dermatitis, dry and scaly skin, and eczema.  


7. Chronic sinus issues

Inhalation of mycotoxins can cause congestion and chronic sinusitis. 

Mold spores can irritate and inflame the mucosal sinus membrane of the nasal passages and trigger sinusitis and other sinus-related symptoms such as facial pain, post-nasal drip, headaches, and loss of smell.

Stomach pain

8. Digestive problems

Mold-contaminated food or airborne mold spores can cause digestive system issues when ingested.

Mycotoxins have been found to stimulate immune cells within the gastrointestinal lining and trigger the release of histamine, which can cause digestive symptoms, including nausea, diarrhea, vomiting, and acid reflux. 

Your immune system is mostly gut bacteria, and mold is believed to disrupt the delicate balance of beneficial bacteria residing in your intestines, increasing the risk of dysbiosis.  

An imbalance of intestinal microflora is linked to digestive disturbances, such as constipation, bloating, and abdominal pain.  

9. Depression and anxiety 

Many mycotoxins have neurotoxic properties and impair normal neuronal functions linked to depressive disorders.  

Neurotoxic mold spores have been found to disrupt normal brain processes and imbalance the production of neurotransmitters such as dopamine and serotonin.

These neurotransmitters are crucial for regulating emotions and moods, and imbalances are linked to depressive symptoms and anxiety.   

10. Migraines 

More research is needed to establish the exact link between mycotoxins and migraines. 

However, it’s believed that certain mycotoxins cause vasodilation—the widening of blood vessels—leading to changes in blood flow patterns linked to the onset of throbbing vascular migraines.  

Time to detox sign

How to detoxify after mold exposure

Do you suspect you have been exposed to mold toxins and are concerned about the potential health consequences of mold allergy?

You can take several steps to support your body’s detoxification systems and help eliminate mycotoxin accumulations.

1. Avoid foods prone to mold and yeast  

A low-mold diet gives your system a break from constant exposure to small amounts of molds that can accumulate in your system and lead to health issues.

Foods at a higher risk of containing mycotoxins include soy, corn, cheese, dried fruits, peanuts, packaged and smoked meats, and alcoholic beverages. 

2. Garlic 

Regularly incorporating garlic into your diet is a great choice to support mold detoxification. 

Garlic contains allicin, a potent bioactive compound with antifungal properties found particularly effective for toxic mold species such as Aspergillus. 

Regularly doing garlic nasal rinses may be beneficial if you suffer from mold-related sinus issues. 

3. Avoid sugars and refined carbohydrates 

Fungi and yeasts thrive on sugar, and a high-carbohydrate diet can worsen the symptoms of mold toxicity, which explains why a high-sugar diet significantly increases the risk of recurring yeast infections such as Candida albicans.   

A low-carb diet like Healthy Keto® doesn’t just starve microbes of its primary fuel source—it also supports healthy liver function needed to detoxify harmful compounds, including mycotoxins. 

4. Natural remedies 

“Depending on the severity of mold toxicity, dietary changes alone may not be enough to detoxify mold accumulations in the body,” explains Dr. Berg.

Luckily, several natural remedies boost detoxification and help to eliminate mycotoxins:

  • Grapefruit seed oil has potent antifungal properties and has been used as a natural remedy for mold-related issues for centuries. 

  • Bentonite clay is made from volcanic ash and is known for its ability to absorb toxins and may help to remove mold spores from the body.  

  • Milk thistle is an amazing herb for liver health. Milk thistle seeds are rich in silymarin, a bioactive compound that helps to neutralize toxic compounds and protects liver function.   

Woman waiting

How long does it take to detoxify after exposure?

How long it takes to detoxify after mold exposure depends on several factors, including the duration and severity of exposure, overall health, and whether you support your body's natural detoxification processes. 

Some people eliminate toxins more efficiently, while others may take significantly longer due to preexisting health conditions, compromised immune function, or genetic factors.

While short-term exposure symptoms are typically resolved within a week or two, detoxification after prolonged exposure to toxic mold can take months and sometimes even years.  

Mold removal

How to neutralize mold in your environment

If you have noticed any mold in your environment, it’s recommended to contact a professional mold remediation company that is licensed and trained in the safe neutralization of mold.

Taking it upon yourself to clean up moldy patches can disrupt mold spores and spread them even further, which can compound the existing mold problem. 

Once mold has been safely removed, there are a few things you can do to prevent new mold growth:

  • Keep your environment dry 

  • Fix any leaks 

  • Use a dehumidifier 

  • Clean up spills immediately 

  • Use mold-resistant materials 

  • Ensure your environment is well ventilated  

Healthcare consultation

When to see a doctor

If you suspect mold exposure and have developed any health issues or experience worsening of existing health conditions, it’s recommended to consult a healthcare provider especially if you have experienced any of the 10 warning signs of mold toxicity listed above. 

Common symptoms of mold exposure include:

Individuals with a weak immune system and preexisting health conditions are at increased risk of developing mold poisoning symptoms and shouldn’t delay seeking medical care if mold exposure may have occurred. 

Moldy bread

Key takeaways

We’ve learned 10 warning signs of mold toxicity. Ingesting or inhaling mold spores from toxic mold species can have serious health consequences and may trigger neurological, immunological, respiratory, digestive, and cognitive issues. 

If you suspect toxic mold exposure, it’s important to neutralize and prevent mold growth in your environment, support your body’s natural detoxification pathways and seek medical support if you are experiencing severe mold allergy symptoms. 


1. How do you tell if mold is making you sick?

It can be challenging to determine if mold is making you sick, as symptoms of mold exposure can vary significantly among individuals.

However, mold toxicity may have occurred if you suspect a potential mold exposure and have developed unexplained health issues or experience a worsening of preexisting conditions.  

2. How do you know if you have toxic mold in your body?

You may suffer from mold toxicity if you have a history of mold in your living or working environment and have developed mold-related symptoms such as respiratory issues, allergic reactions, fatigue, headaches, cognitive difficulties, or gastrointestinal problems.

3. What are the warning signs of mold toxicity?

Mold toxicity can manifest in many different ways, depending on the type and severity of mold exposure and your individual health status. 

Typical warning signs of mold toxicity are unexplained fatigue, cognitive issues, impaired immune function, respiratory issues, and joint pain. 


4. What are the neurological symptoms of mold exposure?

Common neurological symptoms of mold exposure are brain fog, memory loss, heightened light sensitivity, vertigo, anxiety, and depression. 

5. How can I test myself for mold toxicity?

There are no at-home self-test kits to establish if you have mold toxicity, and it’s best to consult a toxicologist to perform laboratory tests to evaluate potential mold accumulation.   

However, there are test kits available to measure mold spore concentration in your environment which may provide some insight into whether you are exposed to mold.  

6. Can your body recover from toxic mold exposure?

Yes, your body has the potential to recover from toxic mold exposure. However, the extent and speed of recovery depend on the duration and severity of mold exposure, your health status, and your body’s detoxification capacities.  

7. How do I detoxify after mold exposure?

You can boost your body’s natural detoxification processes with natural remedies, including grapefruit seed oil, bentonite clay, and milk thistle seeds.

In addition, it's recommended to avoid sugar—a primary fuel source for fungi and yeasts—and limit intake of foods prone to mold, such as grains, peanuts, alcohol, and dried fruits. 


8. How do I get rid of toxic mold in my home?

If you have toxic mold in your environment, it’s best to consult a professional mold remediation company. Cleaning up toxic mold without the right equipment and protective gear can expose you to high concentrations of mycotoxins and may worsen symptoms of mold toxicity.  

9. How much mold exposure is too much?

Some individuals appear more sensitive to mold and experience mold-related symptoms even with low levels of exposure, while others can tolerate higher levels without noticeable health effects. It’s generally recommended to minimize mold exposure as much as possible. 


10. How long does it take to get rid of mold toxicity?

How long it takes to get rid of mold toxicity depends on your overall health and the severity and type of mold you are exposed to. While mild mold-related symptoms can improve within a couple of weeks, more severe cases of mold toxicity can take months and even years to fully resolve. 


11. How soon can mold toxicity symptoms start appearing?

Some people can experience symptoms immediately after exposure, while others may develop symptoms after prolonged or repeated exposure. 

12. Is black mold toxic?

Yes, black mold is a mycotoxin-producing type of mold called Stachybotrys chartarum that is toxic and can cause various health issues. 

13. How do I clear my lungs after breathing in mold?

Your lungs are equipped with immune defenses such as mucus that traps and expels mold spores. You can support your lung health after mold exposure with deep breathing exercises and regular steam inhalation, which opens the airways and helps to clear mucus. 

14. What does mold toxicity feel like?

Mold toxicity can make you feel lethargic and weak, may cause brain fog and light sensitivity, and has been linked to digestive, neurological, and immunological issues.


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