10 Surprising Warning Signs of Mold Toxicity

I see mold toxicity all the time in my virtual functional medicine practice– and often, my patients have no idea they had a mold problem.

Mold exposure can trigger all kinds of different symptoms that affect different systems within the body, from fatigue and brain fog to bloating and weight gain (to name just a few). (1)

Because the symptoms of mold exposure are nonspecific and overlap with the symptoms of other chronic conditions, it’s hard to pinpoint mold as the cause, especially if you’re not aware of toxic mold in your environment (it can hide!).

Mold is shockingly prevalent. If you’re experiencing unexplained symptoms or health issues, or just not feeling like yourself, take a look through this list and see if any of these warning signs sound like what you’re going through.

Remember that not everyone will experience all of these symptoms (and you might have some others that aren’t listed here). But if you’re dealing with some of them, it’s worth looking into mold– and I’ll point you to what to do next if you suspect mold illness or sensitivity.

Let’s get started.

#1. Fatigue

Chronic fatigue is one of the most common– and insidious– symptoms of mold toxicity. It can be easy to brush off tiredness (until it isn’t), and it’s also a sign of so many different health conditions it’s hard to identify the cause.

But especially when combined with some of the other health problems listed below, mold is one of the first places I look when people are feeling consistently fatigued. If you have low energy, often feel run down or like you’re getting the flu, or are experiencing weakness, this might be a warning sign of mold illness.

Studies have also found a strong link between chronic fatigue syndrome (CFS) and the presence of mycotoxins (toxins produced by certain types of mold) in the urine. (2)

#2. Brain Fog

Brain fog, difficulty concentrating, memory loss, and/or impaired cognitive function can indicate that mold is affecting your nervous system. Mycotoxins can trigger brain inflammation and oxidative stress, which can lead to foggy thinking and interfere with cognitive processing. (3, 4)

#3. Dizziness or Ringing in Ears

Mycotoxins from mold can cause other neurological symptoms beyond brain fog and memory problems. Some of the most common examples include dizziness, ringing in the ears, and/or vertigo. Again, these symptoms are thought to be related to an immune system response that creates brain inflammation and neurotoxicity.

#4. Allergy Symptoms

Common allergy-like symptoms of mold illness may include coughing, wheezing, shortness of breath, nasal congestion/sinus congestion, runny nose, respiratory issues, watery eyes, sneezing, or sinus infections.

Allergy-like symptoms and respiratory problems are probably the best known signs of mold toxicity, but it can still be hard to make the connection– you may think you’re just experiencing seasonal allergies. Mold can also exacerbate existing respiratory conditions like asthma.

I also see a lot of patients come in with histamine intolerance or mast cell activation syndrome (MCAS), both of which often present with strong allergic reaction-like symptoms, linked to mold.

LISTEN: Mycotoxin Masterclass: A Functional Medicine Approach To Healing From Inflammatory Mold Illness

#5. Mood Changes

One of the most common symptoms I see when patients are dealing with a mold overload is  sudden or worsening anxiety, depression, or dysregulated moods. Once again, we’re looking at an immune-inflammatory response in the brain that can show up in all of these different ways.

Another neurological effect of mold that often comes alongside mood changes is insomnia or difficulty sleeping.

#6. Digestive Problems

Digestive issues including nausea, abdominal pain, diarrhea, and/or bloating can be warning signs of mold toxicity. Mold can disrupt the balance of the gut microbiome, leading to these and other gastrointestinal symptoms and affecting overall health. (5)

This can create a bit of a vicious cycle– we need a healthy gut microbiome in order to protect ourselves against toxicity from mold exposure. In this way, gut dysbiosis (an imbalance of bacteria in the gut microbiome) can be both a contributing factor to and a result of mold illness.

#7. Headaches

Another common neurological symptom of mold toxicity is headaches or migraines. Some people may experience severe headaches, while for others, this looks more like a dull, low-grade ache that comes and goes (making it another symptom of mold exposure that’s often hard to pinpoint).

#8. Food Sensitivities

I wish I heard more practitioners talking about this one. First of all, certain foods and drinks including nuts, legumes, dried fruits, and coffee, contain mold.

For most people, this isn’t likely to be a problem, thanks to our natural detox abilities. But for those who are already overloaded with environmental mold, or who may be more sensitive to mold because of a genetic variation, these foods can trigger symptoms.

Mold toxicity is also often connected to other food sensitivities, because the body is already in a state of immune reactivity and inflammation.

#9. Unexplained Weight Changes

Mold can lead to weight gain as mold toxins can disrupt the balance and function of hormones associated with metabolism, satiety, and weight control, including insulin and leptin. (6) This can cause the body to store rather than burn excess fat.

In some cases, mold may also lead to unexpected weight loss, also as a result of hormonal disruption or changes to the gut microbiome.

#10. Skin Issues

Skin irritation, hives, itchiness, skin rashes, or redness can occur as a result of mold exposure. Skin issues are often caused by an allergic reaction to mold, but chronic mold toxicity or prolonged exposure can also lead to skin disruptions by triggering inflammation, hormonal imbalance, and gut dysbiosis.

How to Know If Mold Is a Problem For You

Ready to find out if mold is behind your symptoms? There are a few different factors to consider, including:

• Do you have a genetic predisposition that may make you more sensitive to mold?
• Could there be mold in your environment?
• Are there other sources of mold in your day-to-day life that might be contributing?

Several different testing options are available to help solve your mold puzzle. I highly recommend both environmental mold testing in your home and/or workplace, as well as urine and/or blood testing to see what’s going on in your body.

Environmental testing is important so that if you do have a toxic mold problem in your house, office, or another indoor environment where you spend a lot of time, you can immediately get to work either on mold removal or on removing yourself from that environment.

If toxic mold isn’t identified in your current home or workplace, this is good news– but it’s still possible to be dealing with mold illness related to exposure from a past location. Therefore, if mold toxicity is suspected, I would always suggest running urine or blood tests, ideally with a functional medicine practitioner.

Specialized tests can identify the presence of mycotoxins in your urine. This is the best way to see what the situation is like in your body. Genetic testing can also help to identify whether you’re more likely to be sensitive to mold exposure. We all respond differently to biotoxins like mold. Those with HLA or MTHFR gene variations may struggle with methylation and detox, and may need to be more cautious about mold.

READ NEXT: Mold and Oxalates: The Surprising Link That Could Be Affecting Your Health

What To Do Next

If you’ve identified a mold problem, the next step is to eliminate any known sources of mold to the best of your ability. This includes environmental mold in your home or workplace if applicable, and, especially if you’ve identified that you’re more sensitive to mold, food sources and other unexpected mold hiding places.

Even if you have a genetic predisposition to mold sensitivity, you have more power than you may think to beat mold issues. There are several natural steps you can take to boost detox function and improve overall well-being, including dietary strategies and specialized supplements (try The Methylator to enhance detox function). You can learn more about holistic treatment in my guide here.

Mold toxicity can be challenging to tackle on your own. If you’re looking for more personalized support, please reach out to my functional medicine telehealth clinic. We create customized protocols based on the latest research and years of experience working with patients going through mold issues.

As one of the first functional medicine telehealth clinics in the world, we provide webcam health consultations for people around the globe.

Photo: unsplash.com

Sources

• Harding, C. F., Pytte, C. L., Page, K. G., Ryberg, K. J., Normand, E., Remigio, G. J., … & Abreu, N. (2020). Mold inhalation causes innate immune activation, neural, cognitive and emotional dysfunction. Brain, behavior, and immunity, 87, 218-228.
• Brewer, J. H., Thrasher, J. D., Straus, D. C., Madison, R. A., & Hooper, D. (2013). Detection of mycotoxins in patients with chronic fatigue syndrome. Toxins, 5(4), 605-617.
• Ehsanifar, M., Rajati, R., Gholami, A., & Reiss, J. P. (2023). Mold and mycotoxin exposure and brain disorders. Journal of Integrative Neuroscience, 22(6), 137.
• Harding, C. F., Liao, D., Persaud, R., DeStefano, R. A., Page, K. G., Stalbow, L. L., … & Pytte, C. L. (2023). Differential effects of exposure to toxic or nontoxic mold spores on brain inflammation and Morris water maze performance. Behavioural brain research, 442, 114294.
• Liew, W. P. P., & Mohd-Redzwan, S. (2018). Mycotoxin: its impact on gut health and microbiota. Frontiers in cellular and infection microbiology, 8, 60.
• Yang, Z., Hulver, M., McMillan, R. P., Cai, L., Kershaw, E. E., Yu, L., … & Shi, H. (2012). Regulation of insulin and leptin signaling by muscle suppressor of cytokine signaling 3 (SOCS3). PloS one, 7(10), e47493.