Non-Thyroidal Illness Syndrome in Patients Exposed to Indoor Air Dampness Microbiota Treated Successfully with Triiodothyronine


Long-term exposure to molds in water-damaged buildings (WDB) has been associated with numerous health problems including allergic airway symptoms (1–3), fungal sinusitis (1, 2, 4), abnormalities in T and B cells (5–7), infection sensitivity (6, 8), asthma (9–11), respiratory infections (3, 11, 12), central and peripheral neuropathy and polyendocrinopathy (8), neurologic symptoms (1, 4, 13), neuropsychological cognitive dysfunction (CD) (14–16), neuropsychiatric symptoms (3, 14, 17), and chronic fatigue (CF) (6, 14, 18). It is now well established that mold and mycotoxins are important constituents of the milieu in WDB and that they can provoke a huge spectrum of illnesses (3, 8, 12, 15, 18–37).

Exposure to volatile organic compounds including metabolites produced by toxigenic fungi, some of which are inflammatory agents, can lead to a deficiency or imbalance of many hormones, such as insufficient amounts of the active form of thyroid hormone, commonly abbreviated to T3 hormone (38, 39).

Thyroid hormones play a very important role in development, growth, and glucose–fat–protein metabolic homeostasis in all tissues by affecting the expression of many genes. It has been shown that the most important factors in thyroid hormone regulation are the activities of the three deiodinase enzymes (DIO 1, 2, 3). In particular, DIO2 regulates the activities of thyroid hormone action by metabolizing the precursor molecule thyroxine (T4) that is secreted by the thyroid gland into the biologically active molecule, T3. Two of the deiodinases (DIO1, DIO2) contain selenium and are responsible for transforming T4 either into its active metabolite, i.e., T3 or to an inhibitory reversed T3 form, rT3 (DIO3) (40–43). The importance of DIO enzymes in thyroid hormone homeostasis has become increasingly clear by experiments conducted in DIO knockout mice (44). DIO enzymes affect the thyroid hormone regulation by controlling thyroid hormone homeostasis at the cellular level, such as in the case of symptoms in mold exposure or in other situations in which there is a lack of active T3 hormone in the peripheral tissues or brain (45). A deficiency of active cellular T3 hormone has been described as a non-thyroidal illness syndrome (NTIS) (46). The patients with this disease presents with normal function of thyroid or with required exogenous T4 with normal thyroid-stimulating hormone (TSH), free T4 (FT4), and free T3 (FT3) values in the blood, but still with symptoms of hypothyroidism. Importantly, the major part of T3 is generated locally from T4 by DIO2 in most tissues of the body and in the brain, especially at the hypothalamus–pituitary level (47).

The toxins released by the microbes living in damp buildings can induce oxidative stress (OS). OS has been proposed to be one of the most important mechanisms behind the adverse health outcomes associated with living in a damp indoor environment. One of the putative consequences of mycotoxin-induced OS is a blockade of crucial mitochondrial functions (47). OS may cause cytotoxic, genotoxic, and inflammatory responses by increasing the production of reactive oxygen species (18, 48).

Oxidative stress also impacts negatively on various hormonal influences, e.g., causing antioxidant imbalance and impairing the functions of the deiodinase enzymes. For example, OS reduces the capacity of DIO2 to convert thyroxine (T4) into its biologically active form of T3. Different defense mechanisms that protect against the free radical damage have been characterized in various cellular localizations, including the endoplasmic reticulum, mitochondria, plasma membrane, peroxisomes, and cytosol.

There are several enzymes such as superoxide dismutase, catalase and glutathione peroxidase, and transition-metal binding proteins, which rapidly inactivate free radicals (49).

Thus, OS can be defined as a failure of the antioxidant system to cope with the excess of free radicals. One putative hypothesis is that OS facilitates the development of hypothyroidism or rather a lack of availability of the T3 hormone at the tissue level, the so-called NTIS (38). In the 1970s, much of the basic biochemistry of thyroid metabolism was clarified (46, 50). It has been postulated that the level of rT3 and the FT3/rT3 ratio correlate with tissue DIO activities and reflect the peripheral metabolism of thyroid hormones. In a normal physiological situation in the human body, the amount of FT3 should be about 2–2.5 times higher than that of rT3; this represents the optimal level of active T3 in peripheral and brain tissues. In the normal physiological situation, rT3 is metabolized 2.5 times more rapidly than T3, and therefore, the FT3/rT3 calculated ratio should be at least around 2–2.5 (50) (or 20–25, depending on the form or expression).

In insulin-resistant patients, the T3/rT3 ratio is significantly increased in comparison to the corresponding value in insulin-sensitive controls (51). In the treatment of obesity, it has been suggested that attention should be paid to correcting the uncoupling of the mitochondrial respiratory chain (52). For example, in an experimental diet-induced obesity model, higher rT3 concentrations were detected in obese animals, one consequence of which might be reduced by oxygen consumption (53).

Patients who have been exposed for a prolonged time to indoor air molds have high serum levels of rT3 (unpublished observation). This indicates an imbalance between rT3 and FT3 and decreased tissue metabolism of T4 to be converted to T3, in other words NTIS. In these patients, DIO2 does not function properly (45), therefore T3 therapy is indicated. The rationale for T3 therapy is: T3 is biologically active hormone that does not require activity of the DIO2 which is needed for conversion from endogenous prohormone T4 to active T3 hormone, or when exogenous levothyroxine (LT4) monotherapy is administered. I will describe the treatment of patients with diagnosed NTIS due to long-term exposure to dampness microbiota.

— Update: 04-01-2023 — found an additional article Mold: A Potential Trigger of Hashimoto’s from the website for the keyword hypothyroidism and mold exposure.

For many people with Hashimoto’s, the root cause of their hypothyroidism can be linked to dietary triggers. Often times, eliminating problematic foods is key to finding healing and eventual remission. However, there are other toxins that can contribute to the autoimmune response, some of them less obvious than others. One such trigger that we hear about less often is mold.

Though not everyone is sensitive to mold, a surprising number of people will find that their deteriorating health, including respiratory, digestive and cognitive issues, can be linked to exposure to toxic mold. In fact, almost 10 percent of the people with Hashimoto’s that I surveyed said that they had been exposed to mold—and that number only accounts for those that knew they were exposed!

In this article, I’d like to explore the connections between mold and Hashimoto’s, including:

  • The difference between mold versus toxic mold
  • The connection between mold toxicity and Hashimoto’s
  • Dave Asprey’s Hashimoto’s success story
  • Symptoms of mold exposure
  • Diagnosing and addressing mold toxicity

What is Mold?

Molds are a form of fungi and are a natural part of the environment we live in. They can be found almost anywhere, wherever oxygen and moisture are present, and can spread through the air by way of spores, their reproductive cells.

Mold often lurks in damp, dark environments within the home, such as bathrooms, kitchens, recently flooded areas, and basement areas. It can also be found under sinks and in areas with poor ventilation.

Outdoors, mold is often found in moist soil and decaying organic matter. High levels of mold spores in the air are often to blame for environmental allergic reactions. Indoors, when moisture is present, mold can be found in building materials, carpeting, and even foods. Mold can often accumulate when a home is flooded or if there is a hidden water leak that is left unaddressed.

Though molds are all around us, it’s exposure in large quantities that can sometimes lead to serious health problems. Indoors, the most common types of mold typically found are Cladosporium, Penicillium, Alternaria, and Aspergillus. Common health complications related to indoor mold exposure include asthma attacks, headaches, dizziness, sinus infections, and skin rashes.

Some molds produce toxic secondary metabolites called mycotoxins. We call these “toxic molds,” as their mycotoxins can cause serious health problems for both humans and animals. Exposure to mycotoxins has been linked to neurological problems and even death.

Stachybotrys chartarum (sometimes referred to as “black mold”), which grows on household surfaces such as wood, fiberboard, gypsum board, paper, dust, and lint, is one of the most commonly known toxic molds.

Mold: A Potential Root Cause of Symptoms

There are hundreds of peer-reviewed articles discussing the harm that “black molds” are capable of causing to the brain and immune system. The work by mold researcher Dr. Enusha Karunasena has demonstrated that the endothelial cells that make up the blood-brain barrier can become compromised by these molds. Since the endothelial cells make up the brain’s primary protection mechanism against outside threats, damage to them means that the toxic molds can easily get into the brain and damage the neurons.

It’s important to note, however, that not all molds are harmful. In fact, molds have many valuable functions, including pharmaceutical and food production uses. After all, penicillin, soy sauce, and blue cheese wouldn’t exist without the presence of mold! However, those who are sensitive to mold may find that even the small amounts of mold present in cheese, nuts, or coffee may be enough to create an adverse reaction.

Symptoms of Mold Toxicity

When it comes to mold exposure, not everyone is affected in the same way. Even those living in the same home may develop different symptoms depending on their genes. Sometimes, multiple family members in the same household may have varying levels of immune-related diseases, but others may not exhibit any symptoms.

That said, common symptoms of mold exposure include brain fog, respiratory issues, cognitive impairment, immune suppression, fatigue, depression, arthritis, digestive problems, poor sleep, inflammation, and joint pain.

Those who have an allergy to mold may experience watery, itchy eyes, a chronic cough, headaches or migraines, difficulty breathing, rashes, fatigue, sinus problems, nasal blockages, and sneezing.

Some of the clients that I’ve seen affected by mold have shown me unbelievable before and after photos. People who were once thin and athletic can put on weight and collect so much inflammation in their bodies that they become virtually unrecognizable within months of mold exposure.

Read more  Mold: A Potential Trigger of Hashimoto’s

The Mold and Hashimoto’s Connection

An adverse reaction to mold can be a trigger for Hashimoto’s, asthma, and other autoimmune conditions. While I’ve heard a few Hashimoto’s remission stories from readers who were also affected by mold, I was shocked to learn that as many as 45 million people worldwide may be affected!

One of the potential clues of mold being a root cause is when a person’s health begins to deteriorate after moving into a new home. When I conducted a survey with the Hashimoto’s community in 2015, 20 percent of them reported that their health began to decline after a move.

It’s important to note, however, that not everyone is affected the same way when exposed to mold. Depending on a person’s genetic predisposition, they may develop a severe case of asthma, have a sneezing fit, or not experience any noticeable symptoms after a mold exposure.

The mold Aspergillus, commonly found indoors, has been shown in studies to be a cause of thyroiditis in people who were immuno-suppressed. In one study, as much as 20 percent of people affected by disseminated disease were shown to have thyroids that were infiltrated by the Aspergillus mold.

Another study demonstrated that patients who developed chronic illness after being exposed to water damaged buildings and mold were infected with mycotoxins, detectable in urine samples. The study concluded that mold is harbored in the body and continues to release and produce mycotoxins, which contribute to ongoing chronic illness. Sinuses are the favored spot in the body for the mold and mycotoxins to live.

Dave Asprey Shares His Hashimoto’s Success Story

Hypothyroidism and mold exposure

You may have heard of Dave Asprey, biohacker extraordinaire, the creator of Bulletproof, and the author of the New York Times bestselling book, The Bulletproof Diet, but you may not know that Dave was once diagnosed with Hashimoto’s and was able to put it into remission.

I have to tell you that I was a little star-struck when I met Dave Asprey back in 2013. I sat next to Dave at a dinner following a health conference, shortly after releasing Hashimoto’s: The Root Cause. As I began to introduce myself, Dave cut me off: “Yes, you’re Dr. Izabella Wentz, the ‘Hashimoto’s Hacker’. I’m familiar with your work. I recommend your book to all of my clients with Hashimoto’s.”

I nearly fell out of my chair. I excused myself to call my husband, who, like me, was a huge fan of Dave’s popular podcast. Of course, my husband said, “Why are you talking to me? Go back and talk to him!”. Thank goodness for a voice of reason and assigned seating.

I got a chance to spend the evening chatting with Dave and his wife Dr. Lana Asprey, a fertility specialist, over a delicious Paleo dinner, and we became fast friends. It was amazing to see that Dave was just as brilliant and witty in person as he is on his podcast, but also, that he and his wife were kind, passionate and dedicated to helping people.

I also learned two things that fans of his coffee may not know about Dave…

  • Dave USED to have Hashimoto’s and was able to put it into remission.
  • One of Dave’s root causes was toxic mold.

At one point, Dave weighed 300 pounds and was constantly brain fogged and exhausted, despite eating a very low calorie diet and exercising six days a week.

Like many of us, he set off on a quest to find answers, and eventually found an integrative doctor who was able to help. Upon finding out he had Hashimoto’s, Dave went completely gluten free and began to change his lifestyle, eventually leading to the development of the Bulletproof diet. As he saw improvement in his health with diet, Dave’s research continued to lead him toward toxic mold. He knew the house where he was living had toxic mold, and the house where he grew up likely had mold issues as well.

He decided to lessen his mold exposure and was able to turn down his autoimmune response. In addition to looking into ways to reduce environmental exposure, he focused on how changing his diet might diminish his mold burden, and reduced his intake of foods containing mold.

His quest to avoid toxic mold in food led him to create his signature Bulletproof Coffee, a drink low in mold and cross-reactive toxins. He also eliminated high-mold foods and beverages from his diet, including peanuts, raisins, beer, and wine. Additionally, he supported his body with activated charcoal (which helps get rid of mold) and glutathione (an antioxidant). The results were astonishing. Dave is now the muscular poster-boy of high performance and is running a multi-million dollar company. And, his thyroid antibodies are now at zero!

Dave was also behind the creation of MOLDY, a documentary about the health effects of toxic mold to spread awareness about this little-known root cause of multiple health conditions.

Testing for Mold

If you suspect that you have been exposed to mold, like Dave Asprey had been, it’s important that you test both your home environment and your body to see if molds are present.

Mold in the Home

As I mentioned earlier, the most common places for mold to exist in the home are dark, damp places that get limited ventilation, such as bathrooms, basements, and any areas that have been flooded in the past. Many affected homes may have a stale, moldy smell. Though a visual inspection may alert you to the presence of mold, not all mold spores are visible to the human eye. Mold can also be lurking behind walls and under flooring, so it will be important to perform an air quality to test to find out if mold is present in your home.

Additional places that can harbor mold in the home include:

  • Houseplants
  • Christmas trees
  • Carpeting
  • HVAC filters
  • Closets
  • Cardboard boxes
  • Washing machines
  • Water pipes

You may have heard of “toxic black mold” and think that all toxic molds are black and easy to spot. However, this is a myth. Many molds are not visible to the eye and present in a multitude of different colors.

To determine if mold is present in a building space, an air sample is taken by using a specialized pump to collect airborne spores. A lab will then determine both the amount of mold spores present in the air, as well as the species of molds.

Mold testing can be conducted by a professional service; however, there are also home kits available that allow you to test for the presence of mold in your home yourself. Kits can be purchased through Real Time Laboratories, and results will be sent directly to you.

Mold Prevention

To prevent mold growth in your home or workspace, there are several steps that can be taken:

  • All sources of uncontrolled moisture should be eliminated (e.g. roof leaks, pipe leaks, flooding).
  • Keeping indoor humidity levels below 40 percent will inhibit mold growth.
  • All heat/air ductwork systems should be cleaned every two years, and all of the seals on the ductwork should be inspected and repaired, if necessary.
  • Once or twice a week, a non-toxic, bio-balancing spray (such as Citrisafe) should be sprayed into the intakes of the duct system. As the unit pulls air, the spray will circulate and keep mold growth to a minimum.
  • Anti-microbial filters that kill mold spores should be used in your HVAC intakes.
  • Get rid of cardboard boxes. Mold feeds on the ground up wood used to make cardboard, and most people store boxes in under-ventilated spaces, such as garages and closets. Use plastic containers for storage instead.
  • Don’t pack clothing articles too tightly in closets — let the closet breathe.
  • Leave your washer and dryer doors open while not in use, and spray with a bio-balancing spray (Citrisafe) after each use.
  • Don’t clutter corners and areas around furniture with objects that might cause poor air circulation; these areas collect dust and harbor mold.
  • Increase ventilation in bathrooms (open windows, turn on fan) to help remove moisture during and after use.
  • Cold water pipes should be insulated to prevent sweating and water dripping.
  • All pipes entering through flooring or walls (e.g. under the kitchen counter) should be sealed with caulking. The same thing should be done with the metal boxes of all electric plugs and light switches.
  • Indoor plants should be limited, as houseplants can easily grow mold. However, NASA has performed extensive research on plants and toxic air to find plants which would remove harmful chemicals from the air (such as formaldehyde and benzene). The following is a list of the plants they found to be helpful:
    • Bamboo Palm (Chamaedorea seifritzii)
    • Chinese Evergreen (Aglaonema modestum)
    • English Ivy (Hedera helix)
    • Gerbera Daisy (Gerbera jamesonii)
    • Janet Craig (Dracaena “Janet Craig”)
    • Marginata (Dracaena marginata)
    • Mass Cane/Corn Plant (Dracaena massangeana)
    • Mother-in-Law’s Tongue (Sansevieria laurentii)
    • Pot Mum (Chrysantheium morifolium)
    • Peace Lily (Spathiphyllum “Mauna Loa”)
    • Warneckii (Dracaena “Warneckii”)

Mold in the Body

Testing for mold in your home environment is just as important as testing your body for the presence of molds.

Functional medicine testing can help you determine whether the mold from your environment has moved into your intestines. I recommend the GI Effects Gastrointestinal Function Comprehensive Profile (One day collection) METAMETRIX KIT, which can be ordered by a functional medicine physician. Alternately, you can order the test yourself through a company such as Direct Labs.

You can also run a RealTime Laboratories test for mold metabolites in your urine to determine if mold has taken up residence in your body. Additionally, it may be helpful to have your doctor run a mold panel from ALCAT labs to see which molds are reactive in your body. If you’ve done stool testing, sometimes the tests may reveal mold overgrowing in your gut. The mold will show up as “yeast present—taxonomy unavailable.”

A third test that can be ordered online is the MycoTOX Profile. This comprehensive test screens for 11 different mycotoxins, from 40 species of mold, in one urine sample. It uses advanced mass spectrometry (MS/MS) to detect lower levels of these fungal toxins. This test is optimal for follow up testing to ensure that detoxification therapies have been successful.

Treatments to Eliminate Mold

If you’ve been exposed to mold, it is quite possible that the mold has taken up residence in your body. Eliminating your exposure is a critical first step to recovery from mold toxicity.

In addition to removing the source of the mold, you will most likely need additional interventions to clear the mold from your body.

The presence of mold in the sinuses and intestines can lead to intestinal permeability (leaky gut) and become a trigger for autoimmune disease. Sinus infections (sinusitis), which are often triggered by mold, can also be a root cause of Hashimoto’s. In fact, a study conducted by the Mayo Clinic showed that moldy home and work environments were responsible for 9 out of 10 cases of chronic sinus issues.

Read more  Should Thyroid Patients Get The Flu Vaccination?

Fungal Sinusitis

For years, researchers believed that all sinus infections were the result of either bacteria or viruses. Now, they are coming to realize that when fungi like mold enters the sinus cavity, a suppressed immune system can react and result in fungal sinusitis. Fungi love damp, dark conditions, making the sinus cavity a perfect place to grow.

There is almost no way to tell the difference between sinus infections caused by fungi and those caused by viruses or bacteria. Additionally, sinus infections can often have a combination of causes. Symptoms of all three types of sinus infections look the same: headaches, sinus pressure, congestion, and discolored discharge.

Allergic fungal sinusitis was first recognized as a disease about a decade ago. It accounts for approximately 6-8 percent of all chronic sinusitis diagnoses that require surgical intervention. Although certain signs and symptoms may cause a physician to suspect allergic fungal sinusitis, no standards have been defined for establishing the diagnosis. However, it is extremely important to recognize allergic fungal sinusitis and differentiate it from chronic bacterial sinusitis, because the treatments and prognosis for these disorders may vary significantly.

Fluconazole, in particular, is a promising treatment for persistent fungal sinusitis infections. One recent study looked at 16 patients with a history of allergic fungal sinusitis. The patients were given fluconazole nasal spray and were followed for three months. Improvement of disease, without significant side effects, was observed in 12 of the 16 patients. Though larger studies are needed to confirm these results, these preliminary findings show that people with allergic fungal sinusitis may benefit from this course of treatment.

The only way to know for sure whether your sinus infection is caused by mold is to get tested for fungal sinusitis by your doctor. There is a test called MARCoNS (Multiple Antibiotic Resistant Coagulase Negative Staphylococci) that can test for mold related bacterial infections, as well as fungi in the sinuses.

A CT scan (which combines x-rays to view cross sections of the body) with an ear, nose and throat specialist can also help determine if a fungal or bacterial infection is present in the sinuses.

Symptoms of chronic sinusitis include pain in the sinuses, nose, ear, face, or throat, as well as drainage from the nose, headaches, chronic cough, post-nasal drip, sneezing, congestion, throat irritation, loss of smell, and ear inflammation. A person may also have a fever, but that may be missed in thyroid disease.

In some cases, treating this sinus infection can reverse Hashimoto’s.

Supplements to help clear mold from the sinuses and gut include:

  • Argentyn 23 nasal spray: 5-10 sprays in each nostril for 7-14 days, then 2 sprays in each nostril twice daily until infection resolves
  • Oil of oregano: 2 capsules, 3 times per day, for 30–60 days
  • S. Boulardii: 5 billion–15 billion CFUs, 2-4 times per day (up to 8 per day), for 60 days
  • Activated charcoal: 2 capsules at bedtime (may cause magnesium depletion)
  • CholestePure by Pure Encapsulations (soy derived): 1–2 capsules,
    3 times per day (with meals), for 30–90 days

Additionally, some prescription medications may be required to treat the infection:

  • Fluconazole (kills mold in the sinuses and throughout the body)
  • Cholestyramine (binds mold in the body)
  • Doxycycline/Augmentin (treats secondary bacterial sinus infections)
  • Nystatin oral (treats mold in the gut)
  • Nystatin nasal flush (compounded medication used with a NasoNeb to treat fungal infections in the sinuses)
  • Prescription Nasal Spray (compounded medication that includes Sporanox, Xylitol, Bactroban, and Beclometasone, to treat both fungal and bacterial infections in the sinuses)

In addition to these treatments, I recommend implementing a nasal rinse with a neti pot once or twice daily, as well as optimizing gut health.

It may be helpful to work with a practitioner who is specifically qualified to treat fungal infections. For more information on what to look for in a doctor and a few resources for finding a mold doctor near you, please visit the Biotoxin Journey website.

Additional Lifestyle Interventions

Whether you’ve experienced mold toxicity yourself, or you simply want to avoid toxic mold exposure as much as possible, there are several ways you can protect both your living environment and your body from excessive amounts of mold.

Dietary Interventions

Many commonly consumed foods can be contaminated with molds that will increase the toxic burden on the body. Some foodborne molds are obvious. White fuzz on the casserole you found in the back of the refrigerator should probably be avoided! But other foods may contain molds that aren’t visible to the eye. If consumed regularly, these molds can be problematic.

Common mold-contaminated foods include:

  • Coffee
  • Aged cheeses
  • Alcoholic beverages
  • Wine vinegar
  • Condiments
  • Processed meats
  • Mushrooms
  • Packaged fruit juices
  • Dried fruit
  • Leftovers (eat within 24 hours or freeze)
  • Overripe fruit and vegetables (avoid produce that is wilted, discolored, or mushy)
  • Bread
  • Tomato products
  • Multi-B vitamins
  • Products of Aspergillus fermentation (soy sauce, chocolate, black tea, malt extract, Lactaid, citric acid)

All foods will become moldy with time. Therefore, it is important to shop frequently and buy in small quantities. When in doubt about the freshness of the food at your local market, don’t hesitate to ask the vendors about the freshness of their products. Also be aware that organic foods are more likely to mold quickly.

Additionally, following a diet that is low in mold-containing foods (such as the one outlined in Dave Asprey’s The Bulletproof Diet book, which avoids many of the commonly mold-contaminated foods above) can be helpful when you are trying to eliminate molds from your body.

Environmental Interventions

If you’ve discovered mold in your home, it’s likely that you will need to call in a professional mold remediation service to safely remove the contaminated parts of your home. It is critical that the source of exposure be removed in order to heal from mold toxicity. Otherwise, you will be recontaminated and the vicious cycle will continue.

The Environmental Protection Agency website provides more information and a number of resources for detecting mold in your home, methods to clean the mold yourself, and how to find a professional agency to remove mold from your home.

In extreme cases of mold within a home, it may be necessary to move and discard any belongings that have been contaminated with mold. Otherwise, the risk of recontamination can be too great. While this may seem extreme, remember that your health is worth the sacrifice and you will feel so much better once you have eliminated this trigger from your life.

If you are shopping for a new home or workspace, I suggest having the space inspected by a professional mold detection service so that there are no surprises down the road.

It’s also critical that you keep your living space dry and ventilated. Any flooding or water leaks should be immediately addressed to avoid the opportunity for mold to flourish.

Additionally, you will want to have your air ducts cleaned on a semi-annual basis to ensure they remain clear of mold spores.

Using a probiotic cleaning spray, such as Homebiotics, will help kill mold and bacteria on household surfaces. This spray is naturally derived, and safe to use around children and pets.

I also highly recommend investing in a quality air filter, such as the Air Doctor, to help purify your living environment of airborne molds and other allergens. My mother, who has asthma, has seen a reduction in her asthmatic symptoms with it!

The Takeaway

Though mold is one of those unpleasant substances that we’d rather not believe is lurking inside our walls (or inside our bodies!), uncovering the mold in your life could be an important step toward recovering your health and putting your Hashimoto’s into remission.

Testing your home and workspace, eliminating any molds that are present, and being vigilant about preventing mold from forming in your living space are important first steps to becoming free of mold toxicity. Further testing to see if mold is present in your body, followed by implementing a protocol of supplements and pharmaceuticals, may be next steps to ensuring that you eradicate the mold completely.

As always, I encourage you to keep digging for the root cause of your thyroid condition and take the necessary steps to recover your health and vitality!

P.S. You can also download a free Thyroid Diet Guide, 10 thyroid-friendly recipes, and the Nutrient Depletions and Digestion chapter of my first book for free by subscribing to my weekly newsletter. You will also receive occasional updates about new research, resources, giveaways and helpful information.

For future updates, make sure to follow us on Facebook!


  1. What are molds? United States Environmental Protection Agency. Accessed October 15, 2018.
  2. Facts about Stachybotrys chartarum and Other Molds. Centers for Disease Control and Prevention. Accessed October 25, 2018.
  3. Empting LD. Neurologic and neuropsychiatric syndrome features of mold and mycotoxin exposure. Toxicology and Industrial Health. 2009 Oct-Nov;25(9-10):577-81. doi: 10.1177/0748233709348393.
  4. Molds, Mycotoxins & More. Surviving Mold. Accessed October 20, 2018.
  5. Peraica M, Radic B, Lucic A, Pavlovic M. Toxic effects of mycotoxins in humans. Bulletin of the World Health Organization. 1999; 77(9): 754–766.
  6. Winzelberg GG, Gore J, Yu D, Vagenakis AG, Braverman LE. Aspergillus flavus as a cause of thyroiditis in an immunosuppressed host. Johns Hopkins Med J. 1979 Mar;144(3):90-3.
  7. Brewer JH, Thrasher JD, Hooper D. Chronic illness associated with mold and mycotoxins: is naso-sinus fungal biofilm the culprit? Toxins (Basel). 2013 Dec 24;6(1):66-80. doi: 10.3390/toxins6010066.
  8. Forsgren S, Nathan N, Anderson W. Mold and Mycotoxins:
    Often Overlooked Factors in Chronic Lyme Disease. Townsend Letter. Accessed October 25, 2018.
  9. Teitelbaum J. Chronic Sinusitis – Actually a Yeast Infection. The Environmental Illness Resource. Updated March 21, 2013. Accessed October 25, 2018.
  10. Cohen E. Is Mold Causing Your Sinus Problems? Everyday Health. Accessed October 26, 2018.
  11. Petrison L. Losing My Defenses: An Interview with Dr. Enusha Karunasena on the Neurological Effects of Satratoxin. Paradigm Change. Accessed October 20, 2018.
  12. Jen A, Kacker A, Huang C, Anand V. Fluconazole nasal spray in the treatment of allergic fungal sinusitis: a pilot study. Ear, nose, & throat journal. 11/2004; 83(10):692, 694-5.

Note: Originally published in June 2015, this article has been revised and updated for accuracy and thoroughness. 

— Update: 04-01-2023 — found an additional article Mold Exposure Causes Low T3 but can be Treated with T3 Medication from the website for the keyword hypothyroidism and mold exposure.

Is Mold Causing Your Thyroid Problems?

It really shouldn’t surprise you to hear that mold exposure is harmful to your health. 

Read more  Hypothyroidism Nursing Diagnosis and Nursing Care Plans

We now have numerous studies which link exposure to the toxins from mold to many medical conditions including:

  • Chronic fatigue syndrome
  • Infection sensitivity
  • Respiratory infections
  • Immune dysfunction
  • Fungal sinusitis
  • Asthma
  • Neuropathy

And now we can add thyroid dysfunction to that list. 

A recent study from​​ 2017 (1) has clearly shown a link between mold exposure and the development of thyroid dysfunction. 

Why is this important?

Well, in a world where diagnosing thyroid problems is increasingly difficult, you as a patient should be aware of all possible causes to ensure that you get the right treatment. 

We already live in a world where thyroid patients are largely unhappy with their current treatment regimens and we have veteran thyroid patients (those who have had thyr​​oid disease for 10+ years) who report virtually NO improvement in their symptoms despite receiving thyroid medication. 

Understanding this mold connection can serve to help YOU as a thyroid patient because it may help you get on the right treatment. 

The problem with thyroid dysfunction related to mold exposure is twofold:

#1. It causes a thyroid dysfunction lab pattern which most doctors are NOT looking for.


#2. The treatment for this condition is NOT conventional (more on this below).

Let’s talk about each of these and how it relates to you…

This Damage is not Easily Detectable

As I mentioned above, diagnosing thyroid dysfunction from mold exposure is not necessarily easy to diagnose. 

It is but it isn’t. 

Let me explain:

Once you expand your understanding of thyroid lab testing beyond the TSH it becomes very easy. 

But if you are still in the mindset (like most doctors) that the only way to test for thyroid dysfunction is by looking at the TSH then you may completely miss mold-related thyroid problems. 

And the reason for this is simple…

Mold exposure results in a thyroid lab pattern known as non-thyroidal illness syndrome or NTIS for short. 

NTIS can be simply understood as a set of thyroid lab changes that can be caused by multiple medical conditions. 

The fact that you have this lab pattern is not as important as what caused it but you still need to understand what it looks like. 

The problem with the NTIS lab pattern is that you MUST order certain tests that most doctors aren’t accustomed to ordering. 

NTIS will NOT show up with standard lab testing of the TSH and free T4. 

Instead, you need to order further thyroid lab tests including the free ​​T3 and reverse T3. 

NTIS shows up as the following thyroid lab pattern (2):

  • Low free T3 (VERY important finding)
  • Normal to high reverse T3 (usually high)
  • Low to normal free T4
  • Normal TSH

Hopefully, you can see the problem by looking at these labs. 

It’s both possible (and probable) that your doctor could completely miss the diagnosis if they look only at the TSH and free T4. 

If your TSH comes back normal and your free T4 comes back low-normal then you may be flagged as “fine” when the reality is quite the opposite. 

For this reason, it is worth it to fight for the additional lab tests that I have listed above. 

And don’t worry, pretty much all lab companies can order and test for them (and they are covered by insurance). 

If you are having trouble getting these lab tests ordered from your doctor then you may want to print out this study and take it in. 

Treating Thyroid Problems from Mold

Here’s where things get even more interesting. 

The study in question showed that while many of the patients who were exposed to mold received thyroid treatment in the form of thy​​roid medication they didn’t actually see any improvement in their symptoms. 

Put another way:

Their thyroid medication wasn’t working. 

Why is this?

In order to understand why you have to understand just a few quick basics of thyroid treatment. 

The patients who were NOT recovering were taking T4-only thyroid medication. 

And, unfortunately, most people who have thyroid dysfunction take this type of thyroid medication. 

In fact, most thyroid medications prescribed to patients contain only T4. 

You know if you are taking a T4 thyroid me​​dication if you are using levothyro​​xine, Synt​​hroid, Levoxyl, or Ti​​rosint. 

These medications contain ONLY T4 thyroid hormone and these are the medications that do NOT work for those exposed to mold. 

Instead, the study found that it wasn’t until patients started to take T3 thyroid hormone they actually saw some improvement. 

And their improvement was so good that they actually returned to almost a normal state before their exposure. 

4 patients who were on disability were actually able to return to work following treatment with T3 thyroid hormone when T4 thyroid medications failed. 

So what gives? Why the difference?

It’s actually really easy to understand. 

For this to make sense you only need to understand two important facts:

  • #1. T4 is the INACTIVE thyroid hormone and must be activated into T3. 
  • #2. T3 is 300x more biologically active (3) and is really the only thyroid hormone that you should care about. 

Why didn’t T4 medication work for these patients?

Probably for several reasons. 

The first may have a genetic component and the second may be more related to thyroid physiology and function. 

There are simply some individuals, due to their genetics, who simply don’t tolerate T4 thyroid medications. 

We don’t really know exactly how many people fit into this category but estimates put it somewhere between 10% and 20% of ALL thyroid patients. 

And, for those keeping track, this is a huge percentage and may explain why so many thyroid patients even without mold exposure feel crappy despite taking thyroid medications like levothyroxine!

The second reason is probably due, at least in part, to the specific problems that mold exposure causes. 

It seems that mold exposure is more of a chronic condition that results in a chronic inflammatory response. 

The chronic nature of this condition negatively impacts certain thyroid enzymes which are responsible for the conversion of T4 to T3. 

Put in another way:

Mold toxins inhibit thyroid conversion from working properly. 

This means that you can take all of the T4 thyroid medication that you want but the mold prevents your body from activating it. 

It seems that the only way to bypass this problem is by providing your body with T3 directly. 

By doing so you bypass the conversion process and directly provide your body with the T3 that it needs. 

Other Important Therapies

While using T3 thyroid hormone is incredibly important as far as treatment goes, it’s not the only thing you should be aware of. 

The patients in this study not only received T3 thyroid hormone but also received a couple of other therapies. 

In addition to T3 thyroid hormone some patients also received hydrocortisone and DHEA. 

Both of these are hormones (bio-identical) produced by the adrenal glands. 

And even though these therapies aren’t necessary for all people with thyroid dysfunction we can still learn something very important from their use. 

And that is this:

Thyroid dysfunction of any type will almost always cause adrenal-related issues. 

The degree of adrenal gland dysfunction depends on the severity of your thyroid problem, how long you’ve had it, and if the problem affects your adrenal glands directly. 

We know, for instance, that mold exposure probably plays a direct role in dysregulating the adrenal glands which is why these patients needed to use hydrocortisone and DHEA. 

And this degree of dysfunction is typically milder in cases of run-of-the-mill hypothyroidism and Hashimoto’s. 

But the lesson is still important:

You should not neglect your adrenal function and if you are treating your thyroid you should ALSO treat your adrenal glands. 

There are a number of ways to do this and among my favorite are the use of adrenal adaptogens and adrenal glandulars. 

The patients in this study might have benefited from these therapies but they opted for the more aggressive route of using hormones instead of botanicals and herbs. 

Again, what’s important here is that you should be aware that your thyroid and adrenal glands are linked, and if you treat the one you should treat the other. 

And lastly, back to the topic of mold exposure, you should be aware that removing yourself from the SOURCE of mold exposure is priority #1 in terms of treatment. 

The results of this study showed that even though T3 thyroid hormone, hydrocortisone, and DHEA were helpful in making patients feel better, the patients who did the best were the ones who did these therapies PLUS removed themselves from the source of the exposure. 

So keep that in mind if you believe you are currently being exposed. 

Your Next Steps

What does all this information mean to you?

First off, you should be aware that mold exposure causes thyroid problems. 

Secondly, you should be aware that mold exposure requires different treatments compared to regular hypothyroidism. 

And thirdly, you should be aware that this condition exists because it may be playing a role in your body. 

I would say this information is particularly important to ALL thyroid patients who are currently taking thyroid medication and not feeling well. 

Not necessarily because it means that they are being exposed to hidden mold (although this could be true) but because you can draw important information from this study. 

For starters:

The use of T3 thyroid hormone has an important role in the treatment of all thyroid conditions. 

I’ve long been a huge proponent of using T3 thyroid medicines like Cytomel and liothyronine and strongly believe that MOST thyroid patients should use T3 in some form (4). 

In addition, you can use this study as ammunition to help persuade your doctor to change up your treatment regimen. 

Doctors are always hesitant to try “new” therapies (even though T3 treatment isn’t really new) but if they know they have been tried and proven useful then they are more likely to use them. 

And lastly, it just may be that mold is causing your thyroid condition and is something that you should seriously look into and consider. 

Now I want to hear from you:

Does this study surprise you?

Were you aware that mold can cause thyroid problems?

Do you suspect that your thyroid problems may be caused by mold?

Do you have any other symptoms which may suggest mold exposure?

Leave your questions or comments below! 

Hypothyroidism and mold exposure


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About the Author: Tung Chi