Mold toxicity also known as mold illness, occurs when there is exposure to toxins produced by mold spores, called mycotoxins. Mycotoxin exposure can lead to multiple symptoms that include:

Respiratory symptoms such as cough, wheezing and nasal congestion.


Excess fatigue




Cognitive difficulties such as brain fog, poor memory

Focusing difficulty

Joint pain

Burning sensation in skin



Sleep issues

Frequent bronchitis or other respiratory symptoms

Anxiety or low mood

Gastrointestinal symptoms

Neurological symptoms such as numbness and tingling

As you can see from the above list, mold toxicity can cause a variety of symptoms. And there are many health conditions that can cause some of these symptoms. So, mold toxicity is often misdiagnosed or left undiagnosed.

mycotoxin exposure from mold spores
Mold spores

What is the difference between mold allergy and mold toxicity?

Mold allergy occurs when the immune system overreacts when exposed to mold spores. It results in typical allergy symptoms such as sneezing, itchy eyes, nasal congestion, redness and swelling of eyes. Symptoms often appear quickly after exposure. Symptoms also tend to disappear when there is no more exposure.

In contrast mold toxicity results from exposure to chemical metabolites or byproducts produced by mold spores. Symptoms usually take 3-6 months to appear and can last a long time.

Studies have shown that long term exposure to certain mycotoxins can lead to suppression of the immune system and negatively affect kidney function. Some mycotoxins have genotoxic effects, meaning they can damage DNA and increase risk for cancer.

How to test for mold toxicity?

Testing for mycotoxin exposure
Mycotoxin testing

IgE mold allergy test measures the level of IgE antibodies to specific mold species. Although this is an allergy test, for some individuals, this test can be useful in atleast identifying if there has been exposure to mold spores.

To determine mold toxicity, functional tests using urine sample are helpful in identifying various mycotoxins as well as levels present.

Blood tests that test for IgE and IgG antibodies to mycotoxin is another option.

You can also mold test the indoor environment you are in if you suspect chronic mold exposure and resulting mold toxicity.

How do you get exposure to mycotoxins?

You can get exposed to mycotoxins through skin contact, respiration or ingestion of mold contaminated foods.

Hundreds of thousands of mold species are identified in nature and only some of them produce mycotoxins. Of the several hundred mycotoxins identified, about two dozen are of the highest concern.

Who is susceptible to develop symptoms of mold toxicity illness?

I have seen some individuals dealing with chronic symptoms of mold toxicity although there were family members who had no symptoms or develop only minor allergy symptoms when living under the same roof where the mold exposure occurred.

One probable reason for this is individuals with HLA-DR gene, are genetically more susceptible to mold toxicity, which is about 25% of the population.

Factors such as duration of mycotoxin exposure, type of mycotoxin, the health of an individual and the state of gut microbiome also play a role.

How to reduce risk for developing mold toxicity?

An ounce of prevention is worth a pound of cure. This phrase is no truer than in the case of mold toxicity. Typically mold illness develops from environmental exposure. Here are some steps that you can take to reduce exposure.

Mycotoxin exposure from indoor mold growth in air vents/ceiling
Mold growth in vent and ceiling

Reduce indoor mold exposure

  • Watch for signs of mold growth especially in the bathroom walls or windows.
  • Use exhaust fans in the bathroom irrespective of the season, after taking a shower.
  • In summer use dehumidifier in the basement as this is a common area for mold growth in homes. Make sure that the humidity level in your house is optimal- ideally between 30 percent and 50 percent, according to Environmental Protection Agency.
  • Do periodic home inspections to ensure there is no leak in the roof, pipe leaks under the sink or behind your appliances such as washing machine or refrigerator.
  • Make sure the basement floors and crawl spaces are properly sealed and there is no plaster or paint bubbling in the walls indicating presence of excess moisture creating an opportunity for mold to grow.
  • Maintain the air conditioning system in good order and periodically check air vents for mold.
  • It is highly likely there is mold in the building if there is odor of mold present.

Based on your inspection if you find signs of mold growth, you will need professional mold remediation. Even the presence of small amount of toxic mold such as stachybotrys can make you very ill, so get the experts to identify the type of mold and have it removed safely.

To reduce mycotoxin exposure from foods

  • Make sure that foods, especially grains, cereal, nuts and spices are stored properly- kept dry and not too warm.
  • Do not leave perishable food longer than 2 hours outside the refrigerator and no more than 3-4 days in the refrigerator, as per U.S. Department of Agriculture.
  • Ensure a diverse diet that not only reduces risk of mycotoxin exposure but also improves nutrient intake.

Naturopathic Medicine approach to addressing Mold toxicity illness :

Remove the source of mold exposure

Even the best treatment for mold toxicity will not be effective until the source of exposure is removed, making this your primary focus.

Maintain good gut health

Your gut plays an important role in eliminating toxins including mycotoxins from your body.  In the absence of regular and complete bowel movements, this elimination pathway is blocked partially.

Secondly the microbiome, the community of bacteria, yeast and other microorganisms that reside in your gut transform the mycotoxins into less toxic metabolites and helps get rid of these toxins safely. Unfortunately, the interaction between mycotoxins and gut microbiome works both ways. Mycotoxin exposure can also lead to changes in the composition of the gut microbiome.

balance the microbiome
Microbiome in the gastrointestinal tract

Thus, optimal GI function and a healthy microbiome should be supported when addressing mold toxicity, even in the absence of any gastrointestinal symptoms.

Antifungal herbs and nutrients

As mold spores can be present in the nasal pathways or in the gut, herbal antifungals and nutrients such as caprylic acid, pau d’arco, oil of oregano, black walnut, garlic or often a combination of antifungal herbs are used. These antifungal herbs also help by reducing the toxic effects of mycotoxins.

Mold spores may also live in biofilm communities and produce mycotoxins within the body. Hence biofilm disruptors such as grapefruit seed extract and proteolytic enzymes to name a few are used to help degrade the biofilms and make the antifungal treatment more effective.

Naturopathic medicine approach to mold illness using antifungal herbs and nutrients

Antifungal herbs/nutrients

Your health care provider can help select the best suited antifungals and duration of the treatment, based on the mycotoxins involved.

Support Detox Pathways

Your body uses the detoxification pathway to breakdown toxins including mycotoxin to an easily excretable form.

Phase I is the first phase of the detoxification process, that occurs in the liver, where the mycotoxin is chemically altered and made ready for the next phase.

Phase II is the second phase where the mycotoxin metabolite from phase I is transformed into a water soluble and easily excretable form.

Normally our body’s detox pathways are equipped to clear out toxins efficiently. But when the mycotoxin load is high, supplementation with nutrients such as NAC or glutathione, methylation supporting vitamins, and minerals such as magnesium may be required.


Avoid sugar containing foods and reduce starch intake. Mold spores thrive on sugar, using it as fuel. So reducing sugar intake in all its forms will limit the mold growth.

Add Cruciferous vegetables in diet
Cruciferous vegetables

A detox supporting diet high in fiber and cruciferous vegetables and including anti-oxidant rich foods such as berries, green tea, rooibos tea in diet will help support both phases of the detoxification pathways.


Mycotoxin is a fat-soluble toxin that gets excreted into the GI tract via bile. In the intestines, majority of the bile acid gets reabsorbed and returned to the liver. Along with bile reabsorption from stools, any mycotoxin that was eliminated can also get reabsorbed.

This is where binders play a big role in binding and temporarily forming a bond with the mycotoxin containing bile, preventing re-absorption. This “binding” effect ensures that the mycotoxins get eliminated via the stools.

There are a variety of binders that can be used such as charcoal, bentonite clay, zeolite clay, glucomannan, chlorella, humic acid and fiber to name a few. Certain strains of probiotics and mucilaginous foods such as okra can act as binders.

Naturopathic medicine approach to mold illness by using binders

Examples of binders

Selection of binders to be used depends on the type of mycotoxin exposure.

Using binders can sometimes exacerbate constipation, which is another reason that regular bowel movement and good gut health is important for successful treatment.

Your Takeaway

The symptoms of mold toxicity illness are wide ranging. These symptoms could be caused by other factors including lyme disease. So it is important to work with an experienced health practitioner, who can help guide you with the correct diagnosis.

If you suspect mold illness, first remove the source of mold exposure and work with a Health Care Practitioner to support your gut health and detox from the mycotoxin.

The information and other content provided in this blog are for information purpose only, and not intended and should not be considered as medical advice. If you have a medical concern, you should consult with your health care provider before you make any changes to your diet or lifestyle.


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