When Jill Carnahan started getting winded walking up the stairs, she knew she had a problem.
Carnahan, 39, a functional-medicine doctor, was an avid runner, but beginning in the summer of 2014, she couldn’t complete daily tasks without feeling fatigued, out of breath, and weak. She was also getting headaches and catching every virus going around her Boulder, Colo., community.
“I had my suspicions it was mold,” says Carnahan, who had treated mold-related illnesses in her patients. “But I didn’t want it to be.”
Carnahan says she was “in denial for a long time” about the source of her health problems, because she knew a mold diagnosis would likely mean her home or workplace was infested, and the fix was not a simple one.
Even in an arid state like Colorado, mold can wreak havoc on buildings. After Boulder was hit with flooding in 2013, Carnahan saw the first symptoms of mold illness in her patients — respiratory problems, exercise intolerance, a weakened immune system, and new-onset asthma.
When Carnahan started recognizing similar patterns in herself, she tested her urine for mycotoxins, often present after mold exposure. The test was positive.
“A physician cannot base a diagnosis solely on the urine test,” she says, “so I had an inspector come to my work and home.” They found evidence of toxic mold in her office building.
Few others in her medical practice noticed any ill effects. But it turns out that Carnahan had won an unlucky genetic lottery that makes her susceptible to mold illness. About 25 percent of the population falls into this category.
“People like me are really the canaries in the coal mine,” says Carnahan. “We get very sick, and others can be fine.”
Because of Carnahan’s genetic makeup, her body cannot clear biotoxins easily. Mold experts believe the problem lies in the immune system’s response genes. People with this condition usually host a higher “toxic burden” than others because they retain toxins the body would normally clear. This is how Carnahan could get sick from the mold in her building while her colleagues were unaffected.
Carnahan found another office space in January 2015. “Even office papers and documents brought from the old building made me sick,” she says. “I had to completely start over.”
She began an extensive protocol that included dietary changes, nutritional supplements, and detoxifying binding agents to help clear biotoxins from her body.
Nine months after starting treatment, she still follows a strict anti-mold diet, avoiding sugar, most grains, processed food, mushrooms, cheese, and alcohol. Her list of daily supplements remains “two pages long.” But she says she’s 80 percent better and has begun to exercise again.
Carnahan is fortunate: She knew to look for mold as a source of her health issues. For most people, mold-related illnesses remain mysterious and undiagnosed — though this is starting to change. Read on to discover what medical experts are learning about problems with mold, and what they suggest we do about it.
How Mold Can Make You Sick
Mold is everywhere, from the unsightly spores that dot your shower tiles to the tasty blue veins of your favorite cheese. And while mold is one of the earth’s oldest life forms, there is a growing awareness that it can trigger debilitating health symptoms in some people.
Healthcare providers have long considered mold a fringe health complaint, but they are beginning to recognize that as many as a quarter of Americans are susceptible to mold-related illnesses, as well as a condition called chronic inflammatory response syndrome (CIRS).
CIRS is distinct from the simple autoimmune response that leads to allergies, acute sinusitis, or asthma. Mold is a widely accepted trigger for these conditions.
The Institute of Medicine, the Centers for Disease Control and Prevention, and the World Health Organization all recognize the role allergenic molds can play. Many people complain of mold allergies in the fall, when rotting and wet leaves release spores into the air. Antihistamines, immunotherapy, and lifestyle changes are often enough to offset these symptoms.
In contrast, CIRS is triggered by exposure to pathogenic mold. Black mold is the best-known offender in this category, and it is dangerous, but toxic mold can be any color and can grow anywhere with enough water and humidity. These molds can produce mycotoxins, metabolites that are part of the fungi’s growth and can produce an immune-system response that triggers CIRS.
CIRS is a multisymptom, multisystem illness that can leave patients going from doctor to doctor as they try to explain disparate and startling symptoms. Most complain of fatigue, headache, brain fog, digestive problems, and immune-system failures; others can have persistent diarrhea, joint pain, tingling, and numbness.
Often these patients hear that their complaints are all “in their heads.” While many healthcare providers recognize the simple mold allergies that result in runny noses, most aren’t trained to understand the dangers of mold mycotoxins. And those who do are typically outliers in their field.
“The typical patient says this: ‘Doc, you’re my last hope. The neurologist doesn’t know why I’m getting numb, why I can’t remember simple words, and why if I try to vacuum I need to lie down for an hour,’” says Ritchie Shoemaker, MD, a leading voice on mold-related illness in the United States. He’s authored more than 30 papers on mold, and written eight books on the topic, including Surviving Mold (also the name of the website where he reports his research). He’s published several papers that show a link between immune-system-response genes and CIRS.
“In these people, the body is not able to clear the antigens found in damp buildings, including mycotoxins and endotoxins, as it should,” he notes. “Molds can make a toxin, but the body is usually well defended against mold; we should clear these things.”
In the 25 percent of the population that’s genetically susceptible, however, the immune system keeps firing in response to the antigens, creating system-wide inflammation.
Treating and Healing Mold Illness
Because CIRS doesn’t have an established treatment protocol, many patients are left floundering. Different doctors use different treatment plans.
Shoemaker was practicing family medicine in rural Maryland in 1997 when hundreds of patients were exposed to a biotoxin released by Pfiesteria, a dinoflagellate in the Chesapeake Bay and connected rivers. These algae-like creatures can also produce biotoxins that create problems when they are inhaled. Pfiesteria caused an array of symptoms similar to mold illness.
Over time, Shoemaker developed an 11-step protocol to treat illness caused by exposure to biotoxins. It’s based on two guiding principles: Remove the patient from the exposure and administer a binding agent (often the anticholesterol drug cholestyramine) to remove any small toxin molecules in the body. Cholestyramine, which was used to lower cholesterol in the body before statins were prescribed, binds to toxins in the gut. Shoemaker now certifies other doctors in his protocol.
For her mold illness, Carnahan chose to use charcoal and bentonite clay as binders (they can be taken orally), which she acknowledges haven’t been as well studied as cholestyramine but have long histories as tools for detoxification. (Activated charcoal is often used in healthcare facilities to treat food poisoning.) She also boosted her levels of glutathione, a potent antioxidant that supports detoxification.
Bette Bischoff, MD, a functional-medicine physician in Tulsa, Okla., also prescribes charcoal as a binder, and focuses on healing the gastrointestinal tract by restoring the microbiomes of her patients with mold illness. She studies their histories to help chart a course of treatment.
“In taking detailed histories, you learn that they were exposed to mold in a childhood basement bedroom, or by working in a sick building,” she says.
Robert Rountree, MD, a functional-medicine doctor in Colorado, advises caution when dealing with mold-related illness. He notes that its symptoms can overlap with chronic Lyme disease, chronic fatigue syndrome, chronic infections, and yeast allergies, so it’s easy to misdiagnose. He also points out that mold illness involves multiple factors, including genetics, unhealthy microflora, and the extent of exposure. Testing is essential.
“Before diving into an aggressive treatment program, it’s important to confirm the presence of mycotoxins and to determine the impact of these toxins on the person’s immune system and general state of health with the appropriate lab tests,” says Rountree. It’s also critical for patients to identify the source of exposure. “It is pointless to treat a person for mold-related disease without first identifying and mitigating the source of the problem.”
Rountree believes an antimold diet can be helpful for some, but much depends on the individual and his or her circumstances. He emphasizes that patients should not try serious detoxification practices without supervision.
Finally, Rountree counsels patience. “The surprising thing about mold illness is how long it can take to treat,” he says. “Often people improve over six to 12 months, but it can be longer if there’s been an extended period of ongoing exposure.”
Shoemaker hopes that establishing clear diagnostics will help legitimize the disease in the healthcare community. Then, patients can decide which course of treatment they prefer to pursue.
Fighting Mold Where It Lives
The first step to battling mold-related illness is to avoid further exposure.
“Once I make the diagnosis, people say, ‘Wow, that’s fantastic!’ They’re relieved,” says Keith Berndtson, MD, a Chicago functional-medicine physician who’s certified in Shoemaker’s treatment protocol. “But their hearts sink when I tell them that we can’t greenlight treatment until they escape exposure to the mold-related biocontaminants that are triggering their inflammation.”
This can be trickier than it sounds. While there may not be visible black mold creeping up the walls of your home or office building, a surprising variety of places can support the growth of pathogenic molds.
Molds produce toxins only when they have favorable environmental conditions, including water, explains Shoemaker. Indoors, water intrusion is common after flooding, but it can also be found in leaky kitchens, unventilated bathrooms, and humid basements.
Shoemaker cites research showing that 50 percent of all U.S. buildings might host mold. And he points to the DuPont fungicide Benomyl as a possible cause of this problem. In the 1970s, Benomyl (also known as Benlate) was added to paints used in public schools and office buildings to make walls mold-resistant. Based on the evidence available, Shoemaker believes this practice spurred the birth of “super molds,” which produce mycotoxins with an altered chemical structure that’s more dangerous than that of nonmutated mycotoxins. Along with airtight-building practices designed to save money on heating and cooling, new ecological conditions have allowed pathogenic molds to thrive.
When it comes to your home, “you shouldn’t tolerate any mold growth — the key word being ‘growth,’” says Dan Tranter, MPH, a supervisor at the Minnesota Department of Health. “There will always be mold spores in any home, but if you have conditions that are allowing mold — regardless of color, type, or placement — to grow, you need to take care of it.”
This means being relentless about preventing water intrusion in your home, whether that’s from a leaky pipe or a flooded basement. Even the soil in houseplant pots can be hosts for mold.
Tranter doesn’t recommend spending money on mold testing in most cases: “If it looks bad and smells bad, or if you can find the water damage, you can find the mold; focus on that,” he says. “There is no health standard for an acceptable type or amount of mold.”
Homeowners can clean small areas of mold — less than 10 square feet — with soap and water, Tranter says. But any absorbent materials, such as drywall and carpet, that have mold growth should be replaced. Wear a protective mask to avoid inhaling any spores. If you have a mold allergy or suspect you suffer from CIRS, have someone else remove the mold.
More extensive mold may be a candidate for professional remediation, which can be expensive. Tranter recommends researching services carefully, as there are few state or national guidelines for remediation.
“There’s a lot we don’t understand about mold,” Tranter says. So he believes it’s always safer to get rid of it than to let it grow.
Eliminating every bit of mold can be a tall order, but Berndtson says that even a small amount of inhaled biocontaminants can trigger systemic illness once a person has been primed. This makes it an especially tricky foe.
“This is the innate immune system at work,” he explains. “I have patients who know within a few minutes if they’re in a moldy area. The good news is that they can then bow out of a situation gracefully to minimize exposure.” If someone with CIRS starts to feel dizzy, tired, or short of breath upon entering a new space, she’ll know it’s time to go.
Still, even with all the difficulties of ending exposure and beginning treatment, patients facing CIRS head-on find it preferable to wondering endlessly about what might be wrong — and being told repeatedly that it’s all in their heads.
“I can’t emphasize enough how sick I felt,” says Jill Carnahan.
Today she is back on her feet. Even with an illness this complex, recovery is possible. And in the meantime, the more recognition CIRS receives, the more its sufferers are likely to find some much-needed relief.
Keeping Mold in Check
Here are some steps you can take to prevent mold illness, plus tips for what you can do if you suspect you’re suffering symptoms:
- Keep your shower, kitchen, and basement moisture-free and clean. Use a dehumidifier in the basement.
- If you have a small area of mold in your home, have someone who isn’t mold-sensitive remove it with soap and water and dry the surface completely.
- If you have larger areas of mold, flooding or a burst pipe, or standing water, call a professional. The EPA recommends disposing of any material or furniture that has been wet for more than 48 hours.
- If you’ve removed visible mold but still detect a musty smell, have your drywall checked. Make sure remediation professionals are certified by an organization such as the Institute of Inspection, Cleaning and Restoration Certification.
- If you suspect your work environment contains dangerous levels of mold, contact the building manager.
- If you believe you’re suffering from mold-related illness, find a doctor who doesn’t dismiss your ailment. Many integrative and functional-medicine doctors are “mold literate.”
- An antimold diet that removes molds, yeast, most grains and sugars, and fungi like mushrooms can be helpful for some people.