Mold, Mycotoxins & the Biotoxin Illness Explosion

In the tenth episode of *The Healing Terrain*, Dr. Drew Kidder is joined by Laura Frontiero to explore mold, mycotoxins, and why the same environment can affect two people very differently.

Their conversation examines how modern indoor environments may create opportunities for mold growth, the difference between mold and the compounds some molds produce, and why exposure is only one part of a larger clinical picture.

For Frontiero, the response begins with two questions: What is the patient still being exposed to, and does the body have the capacity to respond?

Asked whether mold-related health concerns are increasing or simply being recognized more often, Frontiero’s answer was both.

“Mold is not new to cohabitating alongside humans. There’s always been mold, and there have always been humans.”

What has changed is how people build and occupy indoor spaces. Modern buildings are often designed to be tightly sealed for energy efficiency. When moisture enters through a roof, window, pipe, foundation, or ventilation system, limited airflow and damp materials can create conditions in which mold grows.

“We’ve created the perfect environment for mold to grow,” Frontiero said. “People are inside more often than they’ve ever been.”

The Centers for Disease Control and Prevention notes that mold can grow on drywall, ceiling tiles, wood, insulation, carpet, fabric, and other materials when sufficient moisture is present.¹

At the same time, clinicians and patients have become more aware of how a home or workplace may influence health.

“I think we’re getting a little wiser and better at identifying mold as well.”

Frontiero began her career as a nurse practitioner in conventional medicine. Looking back, she recognizes how rarely the patient’s environment entered the conversation.

“When I worked in Western medicine all that time, I never really asked about the environment.”

Patients might see different specialists for sinus concerns, digestive symptoms, fatigue, poor sleep, respiratory symptoms, or cognitive complaints. Each specialist would evaluate one part of the body, but the larger pattern could remain unclear.

“These people show up as the mystery person. They’ve seen 10 practitioners. They’ve tried working on separate systems.”

Frontiero now looks at the body and the patient’s history as a whole. One of her first questions is when the problem began.

“When did this start? Where were you? What happened when all of this started?”

A patient may remember that symptoms appeared after moving into a new home, beginning a new job, experiencing water damage, or spending more time in a particular building.

That timing does not prove mold is the cause. It may, however, identify an exposure worth investigating alongside other medical possibilities.

The terms *mold* and *mycotoxins* are often used interchangeably, but they are not the same.

Mycotoxins are secondary metabolites produced by certain molds under certain environmental conditions.² Not every mold produces mycotoxins, and the amount produced can vary according to the species, substrate, temperature, humidity, and other conditions.

“Mycotoxins are compounds that molds produce,” Frontiero explained. “Finding mold in your environment doesn’t automatically mean that mold is producing large amounts of mycotoxins.”

Mold itself can also affect health. Spores, fungal fragments, allergens, irritants, and other substances associated with damp buildings may contribute to respiratory symptoms, allergic reactions, asthma exacerbations, or other health concerns. People with compromised immune systems or chronic lung disease may also be at greater risk of fungal infections.³

“The spores of the mold and the fragments of the mold can be irritating,” Frontiero said. “People can be allergic to it, and it can cause respiratory irritation.”

The distinction is important because indoor dampness is a complex exposure. A water-damaged building may contain mold spores, fungal fragments, bacteria, allergens, volatile compounds, and degraded building materials—not one isolated substance.

Indoor environments are not the only potential source of mycotoxin exposure. Mycotoxins can occur in agricultural products and foods, particularly when crops are contaminated before harvest or stored under conditions that permit fungal growth.

Frontiero named grains, coffee, certain fruits, and other stored foods as possible sources.

“Anything that’s going to be sitting for a long time waiting to be processed or being processed” may warrant attention, she said.

For example, patulin is a mycotoxin associated primarily with damaged or mold-contaminated apples and apple products. Regulatory monitoring, appropriate food handling, and removing visibly spoiled foods help reduce dietary exposure.

The presence of a particular mycotoxin does not, by itself, establish where an individual encountered it. Exposure history and environmental context both matter.

Two people can occupy the same building and have very different experiences. One may report significant symptoms while the other notices little or no effect.

“Exposure is important, but the resilience of the person is going to determine what happens after the exposure,” Frontiero said.

Individual responses may be influenced by:

• The type, amount, and duration of exposure
• Allergies or asthma
• Immune and respiratory health
• Genetics and age
• Nutritional status
• Existing health conditions
• Sleep and physical activity
• Other simultaneous exposures or stressors

Frontiero refers to these combined factors as the patient’s “resilience bucket.”

“One person might be sleeping well; the other person might not. One person might be really good at eating healthy; the other person might not. One person may be active and athletic, and the other person may be completely sedentary.”

The model helps explain why exposure alone does not predict the same outcome for everyone.

Inside that bucket, Frontiero also considers “nutrient and mineral status, mitochondrial reserve, antioxidant capacity,” digestive function, and the body’s pathways of elimination.

These factors should not be interpreted to mean that a person caused their response or could prevent every effect through lifestyle. They offer practitioners a way to think more broadly about why susceptibility and recovery may differ.

Frontiero emphasized that a health protocol cannot substitute for addressing an ongoing environmental source.

“You’ve got to get it out of your home.”

For many patients, investigating their home is emotionally and financially difficult.

“This is your safe place, your haven, your beloved home,” she said. “It almost feels like a betrayal to find mold in your home.”

When visible mold, musty odors, leaks, or water damage are present, public health guidance recommends correcting the source of moisture and safely removing damaged material. The CDC does not recommend routine mold sampling because there are no established health-based standards for acceptable quantities of indoor mold. A careful moisture and building assessment is often more useful than relying on air samples alone.¹

Depending on the extent of the problem, patients may need help from qualified building, indoor environmental, or remediation professionals.

Frontiero’s larger point is that ongoing exposure must be considered at the same time as the patient’s health.

“The cost of remediation is not cheap, but the cost of illness is also not cheap,” Dr. Kidder said.

Frontiero cautioned against treating suspected mycotoxin exposure by immediately adding a binder and assuming the problem is solved.*

“There’s no point in binding what cannot be removed. Are you binding something for the sole purpose of binding it, or are you binding something for the purpose of excreting it?”

Binders are designed to adsorb certain compounds within the gastrointestinal tract and carry them out through the stool. But their use does not replace the need to address the source of exposure, support regular elimination, or evaluate the patient’s broader health.

“I thought all I needed to do was give people a binder, and that would solve the problem,” Frontiero said of her earlier clinical work. “But the problem is, if people don’t have open pathways to get that toxin out once it’s bound up, then it just recirculates.”

Although the specific behavior of a compound depends on its chemistry and how the body metabolizes it, Frontiero’s practical takeaway is straightforward: practitioners should assess elimination before increasing the intensity of a protocol.

Drainage Comes Before Deeper Detoxification

Frontiero described drainage as one of the most important changes in how she approaches complex patients.

“You must have open drainage pathways before you start killing or binding.”

Her assessment includes bowel regularity, hydration and urination, liver and bile flow, and lymphatic movement. She generally spends time supporting these systems before beginning a more intensive protocol.

“Before I will ever attempt to do any type of heavy detoxing, people need to be on drainage support first.”

She finds that this foundational stage is often when patients begin to notice meaningful changes.

“We’re getting them pooping, we’re getting their lymphatic system flowing, we’re getting their liver working better. Everything starts feeling better before we start doing the deep work.”

New or worsening symptoms during any protocol should not automatically be labeled a detox or Herxheimer reaction. They may signal an adverse effect, an interaction, excessive intensity, or another health issue requiring evaluation.

Detoxification Requires Cellular Energy

Drainage is only one part of Frontiero’s framework. She also focuses on the energy required to carry out the work of repair and elimination.

“Anytime you’re asking your body to do something above and beyond the status quo, that is going to cause you to have a higher energy demand.”

Mitochondria produce most of the ATP used to power cellular processes. Organs involved in metabolism and elimination—including the liver, kidneys, and gastrointestinal tract—depend on that energy to perform their normal functions.

“There is a cost for repair. There is a cost to move [unwanted compounds] out of the body, and you’ve got to pay with mitochondrial energy. There’s a currency.”

That is why Frontiero pairs support for elimination with support for cellular energy rather than viewing them as separate goals.

“It is so important that you work with a practitioner who not only opens your drainage pathways but supports mitochondrial energy production right along with your protocols.”

Mold May Be One Piece of a Larger Puzzle

Frontiero does not always view mold exposure as the sole explanation for a patient’s health challenges. Sometimes it is one stressor acting on a system that was already under strain.

“Mold can be the final insult that tips a totally overburdened system.”

This may help explain why removing someone from a damp environment does not necessarily result in an immediate return to health.

“Removing the mold from the environment or removing the mycotoxin from the body does not always immediately restore health because there was already an overburdened system.”

Nutritional deficiencies, sleep disruption, digestive concerns, immune health, other exposures, and underlying medical conditions may still need to be addressed.

For practitioners, the lesson is to avoid replacing one narrow explanation with another. Mold may be clinically relevant without being the patient’s only problem.

Sequence Matters

Dr. Kidder summarized the clinical strategy in two words: sequence matters.

Frontiero’s sequence begins by investigating and reducing ongoing exposure. She then looks at drainage, elimination, mitochondrial energy, nutrition, and the other factors shaping the patient’s resilience before advancing into more intensive support.

“Human physiology follows sequences and patterns,” Dr. Kidder said.

The exact sequence must be individualized. Patients with respiratory symptoms, allergic reactions, infections, or other medical concerns may need conventional testing and treatment in addition to environmental interventions and foundational support.

Find the Corner Pieces First

For patients who have been struggling for years, Frontiero closed with the image of assembling a thousand-piece puzzle.

“A lot of people are picking up one puzzle piece and trying to find where it goes, and then putting it down and walking away in frustration.”

The complete picture rarely comes from one test, one product, or one explanation.

“Usually, it’s not one thing that’s going to solve this for you. There are several pieces that fit together.”

Dr. Kidder extended the analogy: most people begin a puzzle by building its outer edge. That framework makes it easier to understand where the remaining pieces belong.

“Find your corner pieces first,” Frontiero said.

For patients and practitioners, those corner pieces may include the environment, regular elimination, cellular energy, nutrition, sleep, movement, and an appropriate medical evaluation.

Frontiero’s final message was one of persistence.

“I never want to hear a no. I want to hear a ‘not yet.’ I haven’t figured it out yet.”

Listen to the Full Episode

Mold, Mycotoxins & the Biotoxin Illness Explosion is available on DrTalks, Apple Podcasts, Spotify, and YouTube.

1. Centers for Disease Control and Prevention. Mold. National Center for Environmental Health. Updated September 26, 2024. https://www.cdc.gov/mold-health/about/index.html
2. Bennett JW, Klich M. Mycotoxins. Clin Microbiol Rev. 2003;16(3):497-516. doi:10.1128/CMR.16.3.497-516.2003
3. National Institute for Occupational Safety and Health. Health Problems: Mold. Centers for Disease Control and Prevention. Updated February 25, 2025. https://www.cdc.gov/niosh/mold/health-problems/index.html
4. Mendell MJ, Mirer AG, Cheung K, Tong M, Douwes J. Respiratory and allergic health effects of dampness, mold, and dampness-related agents: a review of the epidemiologic evidence. Environ Health Perspect. 2011;119(6):748-756. doi:10.1289/ehp.1002410
5. World Health Organization. WHO Guidelines for Indoor Air Quality: Dampness and Mould. Copenhagen: WHO Regional Office for Europe; 2009.

*These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease. This content is for educational purposes only and is not a substitute for individualized medical advice, diagnosis, or treatment.