I recently joined Annika Taylor on The Wellness Rebel Podcast to talk about mold toxicity, and how it can cause not only physical symptoms, but also brain symptoms such as anxiety, depression, OCD, brain fog, mood swings, and in more severe cases, psychosis.

Watch the full conversation above. Below is a recap of our conversation, along with the resources we discussed along the way.

Chapters:0:00 Introduction to Mold and Mental Health1:47 Understanding Mold Exposure and Illness5:13 Personal Journey with Mold Illness8:40 Sources of Mold Exposure12:12 Physical Symptoms of Mold Toxicity18:54 Mental Health Impacts of Mold Exposure25:32 Identifying Mold in the Environment32:28 Treatment Options for Mold Toxicity

I. What Is Mold-Related Illness?

Mold-related illness can be broken down into three distinct categories that often get lumped together: mold allergy, mold toxicity, and mold colonization. Mold allergy, which most people are familiar with, is a reaction to outdoor or indoor mold spores. Mold toxicity is different: it happens when mycotoxins actually accumulate in the body, something that appears to affect roughly 25% of people who can't effectively remove the toxins on their own. This explains why one family member in a home with mold can get seriously ill while another in the same house is fine. Third is the lesser-known mold colonization, where mold spores take hold directly in the sinuses or even the GI tract. That means a person can be out of a moldy environment for years and still have an internal source of toxicity.

II. My Own Mold Story

My interest in mold began around 10 years ago when I was diagnosed with mold toxicity. For years prior, I had been dealing with chronic fatigue, symptoms of fibromyalgia, and vague neurological symptoms that neither my doctors nor I could explain. My daughter was also having complex chronic health issues that initially looked like developmental regression. Understanding the microbiome and dietary changes were helpful to both of us, as were the Walsh Research Institute's nutrient-based interventions, but the real turning point came when the topic of mold toxicity came across my radar in 2016.

Mycotoxin testing and testing of our home and my office confirmed that we had significant exposure and toxicity, which we were treated for and benefited significantly from.

III. When a Partner Isn't on Board: How Mold Treatment Affects the Whole Family

One thing that doesn't get talked about enough is how difficult it can be for someone to get out of or address an exposure if their spouse or partner is not on board. In my own case, I was fortunate — my then-husband was agreeable, especially when he realized how much clarity, decisiveness, and even sense of urgency I had. We'd dealt with significant health issues for a long time, and I didn't want something irreversible to emerge that would leave me in regret for not acting sooner. We acted on that instinct.

We were very lucky to find that we were eligible for insurance coverage, which covered an extended-stay hotel while we had our home remediated. For a lot of families, that's not the reality. If a partner isn't on the same page, it can become one of the biggest reasons someone doesn't end up leaving a house with mold — whether that obstacle gets talked about openly or not. There are those who don't believe mold toxicity is real, and those who don't want to believe it's real (consciously or unconsciously). Education, input from those with expertise, or even seeking couples therapy can be necessary.

It is important to remember that part of the treatment, namely addressing mold in the home, impacts the whole family.

IV. Where Mold Hides: Common Sources of Exposure

For most people who test positive for mold toxicity, the primary exposure is likely environmental, as opposed to mold in food. Leaks under sinks, problems around windows, roof leaks, chimney flashing, damp basements, and high ambient humidity are all common culprits. High humidity left unaddressed can be a big problem. Estimates of the percentage of homes that mold have crept up over the years, from 50% to 75% to, as some consultants now say, essentially every building to some degree. I've seen a couple of children with developmental issues who had mold in their mattresses from bedwetting.

V. The Physical Symptoms of Mold Toxicity

Mold toxicity often shows up as sinus issues (especially with colonization), asthma, and — notably in young children — recurring croup (spasmodic croup) and ear infections.

Many people with mold toxicity also develop mast cell activation, which triggers an exaggerated immune response affecting the skin, respiratory tract, GI tract, and/or bladder. Racing heart, air hunger, and stomach pain can occur. Neurological complaints can include electric "jolt" sensations, numbness and tingling, headaches, light sensitivity, and temperature dysregulation.

Many of these symptoms overlap with Lyme disease, EMF sensitivity, and other chronic conditions. The immune dysregulation caused by mold toxicity can contribute to a vulnerability to Lyme and its coinfections, Candida, SIBO, PANS, PANDAS, and more.

VI. The Brain and Mental Health Symptoms of Mold

Brain Fog, Fatigue, Anxiety, OCD, Psychosis, Mood Swings, Developmental Delays & Cognitive Decline

I don't know what psychiatric symptom mold toxicity can't cause. Brain fog and fatigue are especially common, as is anxiety. For some, mold toxicity can contribute to psychosis and/or dramatic mood swings. In children, mold toxicity can look like ADHD, anxiety, or developmental delays.

I see mold toxicity as something that aligns with — and amplifies — someone's existing genetic vulnerabilities rather than acting alone. Most of the patients I see with severe conditions like schizophrenia, bipolar disorder, or severe OCD have mold toxicity as a contributing factor, though, again, rarely the only factor.

The Neurotransmitter Connection

Mold toxicity can drive up pyrrole levels, which in turn depletes zinc and B6 — two nutrients essential for neurotransmitter functioning. It can also worsen copper-zinc imbalances through oxidative stress and interfere with methylation, both of which also impact neurotransmitter functioning.

A Client's Story: OCD and a Hidden Leak

Annika recalls when she became interested in helping those with mold toxicity. She shares the story of a friend whose severe, debilitating OCD — along with episodes of derealization and out-of-body sensations — turned out to trace back to black mold discovered behind a washing machine, the result of an old water leak. Once they addressed the mold, the connection became clear in hindsight.

VII. Mold Toxins Can Create a Threat Response in the Body & Brain

While we can have threats on the outside, mold toxicity is a threat we can have on the inside. When we are under threat, three systems tend to get activated: the immune system (as discussed with mast cell activation), the limbic system, and the autonomic nervous system. The limbic system puts the body into a vigilant, threat-scanning state — and for some people, that vigilance surfaces as OCD (an unconscious attempt to "make things right" when the body senses something is wrong), health anxiety, or a diffuse sense that something isn't okay.

The autonomic nervous system, meanwhile, can get stuck in fight-or-flight or shutdown mode instead of rest-and-digest. Annika is careful to frame this not something to fear, but something to understand — the goal isn't panic, it's empowerment.

VIII. Testing for Mold: Home and Body

Testing Your Environment

If there's visible water damage or visible mold, extensive testing usually isn't necessary. Generally, where there is water damage or water retained in a space, there will be mold growth. The priority becomes proper containment, and remediation. If there is no known issue and someone has mold toxicity (which could be from an old exposure), I recommend the ERMI-style dust test (I use Mycometrics), which measures water-damage-associated spore counts against outdoor spore counts from a simple cloth dust sample.

I caution against relying solely on air sampling from a home inspector, which I and many of my patients have found unreliable by itself — surface or dust testing gives a clearer picture. Petri-dish testing (I use Immunolytics) can help pinpoint which room is affected, though it misses a couple of important mold species.

Testing Your Body

For testing mycotoxins in the body, I use RealTime Labs, an at-home urine test that screens for five toxin families. Annika discusses her experience with another company, which showed false negatives — a patient with a "no mold" result went untreated for years while ongoing exposure continued.

To improve the accuracy of the test, I sometimes have patients do a sauna session or take glutathione in the days leading up to testing, to help mobilize toxins — though this isn't appropriate for everyone, particularly more sensitive patients.

IX. Treatment: Binders, Antifungals, and Diet

Environment:

Once someone has a positive test and a known or suspected source, I recommend having a consultant (separate from the remediation company, to avoid conflicts of interest) create a remediation plan — ideally with proper containment so the remediation process itself doesn't spread spores further. After remediation, a retest should be done to confirm the space is actually clean, ideally at the remediation company's expense if it isn't.

Binders:

On the body side, treatment typically starts with binders — chosen based on which toxins showed up on testing — such as bentonite clay, activated charcoal, chlorella, or cholestyramine (a prescription option that binds ochratoxin particularly well). I start sensitive patients low and slow, since mobilizing toxins can temporarily worsen symptoms.

Antifungals When Appropriate:

Depending on the response and whether colonization is present, treatment may progress to nasal or systemic antifungals.

Diet:

Because colonization is so common, minimizing sugar and refined carbs is very important, since these feed Candida and mold colonization directly. Foods with higher trace mold content — corn, peanuts, dried fruit, aged meats and cheeses, coffee, and non-shelled nuts — are also worth limiting, along with high-histamine foods for those who are histamine-reactive.

X. Where to Learn More

As Annika emphasizes: this isn't about fearing every corner of your home — it's about being empowered with the right information.

And as always, I welcome your thoughts, experience and questions.

Until next time,

Courtney

Courtney Snyder MD is a Holistic and Functional Child and Adult Psychiatrist who offers non-patient consultations to individuals and practitioners nationally and internationally in addition to her treatment practice serving FL, IN, KY, OH. Her educational content, shared through her website, Substack Newsletter, the Holistic Psychiatry Podcast and her YouTube Channel reaches readers and listeners in over 160 countries.

Resources

* Dr. Courtney Snyder's blog: How Mold Toxicity Impacts the Brain

* Home mold test (dust sample / ERMI-style)

* RealTime Labs mycotoxin urine testing

* Mold Symptom Questionnaire (Dr. Jill Crista)

* Mold Clean-Up Guide (Dr. Jill Carnahan)

* Finding mold consultants & remediation professionals (ISEAI)

* Annika Taylor’s website: Nourished by Nature

Medical Disclaimer:

This newsletter is for educational purposes and not intended or implied to be a substitute for professional medical advice, diagnosis or treatment for either yourself or others, including but not limited to patients that you are treating (if you are a practitioner). Consult your own physician for any medical issues that you may be having.

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