From Asthma to Fatigue, Skin Issues, and More: How Kids’ Unique Physiology Shapes Mold Reactions

by Diedre Bloomquist, FNTP, MRHP, MBCE, PN-L1, IIN HC, CCFT

Ellie was 14 months old when her parents first reached out to us. Her eczema had started around six months as a few rough patches behind her knees that her pediatrician called “typical eczema” and told her parents she would probably just grow out of it. By her first birthday, it had spread to her cheeks, her wrists, and the soft folds of her neck. She scratched through the night, so they went back to the pediatrician, where they were prescribed topical steroids, which worked for a week, but then stopped working. Her parents had already pulled dairy, then eggs, then swapped every soap and detergent in the house hoping to give her some relief.

We asked whether there was any known mold or water damage in the home, but no one else in the family had any health concerns. Mom felt fine. Dad felt fine. Her older brother had never had so much as a rash. “If something in our house were making us sick,” her mom asked, “wouldn’t we all be sick?”

It’s a completely reasonable question, and it’s also the question that leads so many families away from the answer.

When we looked at Ellie’s gut health, it told a much bigger story than her skin did. Her gut was struggling in ways that didn’t match a toddler eating a simple, mostly whole-food diet. As we followed that thread, it led us to mold. We’ll come back to what her family found, but first it helps to understand why Ellie was the only one reacting.

Kids Aren’t Tiny Adults

It’s natural to think of children as smaller versions of us, with the same body running at a smaller scale, but that’s not how their bodies work. A child’s lungs, liver, immune system, gut, and brain are all still under construction. They’re built to grow, not to withstand the same load an adult body can.

That’s why kids are so often referred to as “the canary in the coal mine.” Miners once carried canaries underground because the birds showed signs of toxic gas long before the people around them did. The canary wasn’t weak. It was sensitive in a way that protected everyone else.

So, when a child is the only one in the family struggling, we don’t see that as a reason to rule out the environment. We see it as one of the first reasons to look closer.

Pound for pound, children breathe more air than adults do. They eat more food and drink more water relative to their size, too. So, when the air, dust, and surfaces in a home carry mold spores and mycotoxins, a child takes in a larger share for their body.

Here’s what that looks like in real numbers. A typical 14-month-old weighs about 22 pounds and breathes 24 to 40 times a minute. Her dad, at around 180 pounds, breathes 12 to 20 times a minute. Over a full day, he moves more total air than she does, roughly three times as much. But he’s also about eight times her size. Pound for pound, that toddler takes in about two and a half to three times as much air as her dad, and every spore and mycotoxin particle in that air comes along with it.

Now add where each of them spends their time. Between overnight sleep and naps, a toddler can spend 12 to 14 hours a day in one room. Dad sleeps seven or eight hours in a different room and is gone much of the day. If the problem is in or near the nursery, she’s breathing that air for more than half the day, while he encounters it only rarely. Same house, nowhere near the same dose.

Now think about where kids spend a lot of their time. They’re crawling across carpet, playing on the floor, and pressing their faces into rugs and couch cushions. Household dust is where mycotoxins tend to settle, and for a baby or toddler, that dust is their whole world. Add the constant hand-to-mouth habits of little ones, and you can see how two people living in the same house can have completely different exposures.

Slower to Clear, but Quicker to Build Up

A bigger dose would matter less if kids could clear toxins as efficiently as adults, but they can’t. The liver relies on a two-phase process to break down toxins and package them for elimination, supported by antioxidants like glutathione that help neutralize them along the way. In young children, these systems are still maturing. They work, but not at full capacity, and not at adult speed. So more comes in and less goes out. Over time, mycotoxins can accumulate in a child’s body far faster than they would in a parent living under the same roof.

Some mycotoxins raise the stakes even further. Trichothecenes, a class of mycotoxins produced by molds like Stachybotrys (the one most people call “black mold”), are remarkably potent. They interfere with how cells make proteins, which hits hardest in tissues that renew quickly, like the gut lining, the skin, and immune cells. It doesn’t take much to cause problems, especially in a small developing body.

It’s also why we never take “we don’t see any mold” as a clean bill of health. The most significant growth is often hidden behind walls, under floors, or inside HVAC systems, quietly doing its work where no one thinks to look.

The Exposure That Came Before the House

Theo was two when his mom brought him to us. He’d been uncomfortable almost from birth. He had colic in his first weeks, reflux that never fully resolved, and started developing eczema by three months. He’d never been a good sleeper, and his parents couldn’t remember the last time any of them had slept through the night. They’d already wondered about mold and had their home inspected, but it came back clean.

As we walked through his history, his mom mentioned something almost in passing. She’d spent her pregnancy in an apartment with a slow leak under the kitchen sink. They’d found it, reported it, and moved out a month before Theo was born. It had never occurred to her that it could still matter, but it can.

Some mycotoxins can cross the placenta during pregnancy and pass into breast milk. That means a baby can begin life already carrying a toxin burden, with a detox system that isn’t yet equipped to clear it. When a child has struggled since day one, we don’t only ask about the home they live in now. We ask where mom lived while she was pregnant and before she even conceived her child.

If you’re nursing, please hear this part clearly. Breast milk remains one of the best things you can give a developing gut, and none of this is a reason to stop. It simply means that mom deserves support, too, and that her history is part of her baby’s story.

For Theo’s family, this changed everything. They’d been searching their current home for an answer that wasn’t there. We found elevated mycotoxins in his system, but the exposure happened before he was born and his little body was still working through it.

When Allergies Don’t Make Sense

Maya was six when her parents came to us with a list of diagnoses that kept getting longer. She developed asthma around age four, seasonal allergies that seemed to last all year, and they received an allergy panel that came back positive for dairy, egg, dust mites, and several tree pollens, but most confusing of all her testing came back showing she was allergic to their family dog.

None of it fit. No one else in the family had allergies or asthma, and despite all those positive results, Maya had never had a classic allergic reaction to anything. She’d get congested, itchy, wheezy, and puffy around the eyes with a rash behind her knees that never seemed to really get worse or go away. Her body seemed to be reacting to everything at a low level all the time.

A child’s immune system is still learning. In the first years of life, it’s meeting thousands of new things for the first time and deciding which ones are safe. That learning process makes kids more reactive by nature. When a toxin burden like mold gets layered on top, it can push the immune system into a heightened, hypersensitive state, where it flags things as threats it would otherwise tolerate. The dog didn’t change, but Maya’s immune system did.

This is why a positive IgE result without a corresponding severe reaction warrants closer review. Sometimes it reflects a true allergy. Other times it reflects an immune system that’s overwhelmed and sounds the alarm at everything within reach.

The Kid Who’s Always a Little Sick

Owen was five, and he’d had ear infections every few months since he was a baby and strep twice in the past year, with round after round of antibiotics in between every infection. He was eating only five foods: plain pasta, crackers, chicken nuggets, apple slices, and one specific brand of yogurt. He’d slid from the 50th percentile for weight down to the 15th and was waking two or three times a night. His kindergarten teacher had mentioned he struggled to focus, and at home, small things set off big meltdowns.

His parents had done everything right. They’d addressed each problem as it came. They’d talked with an ENT about ear tubes, started a feeding therapist for the picky eating, overhauled bedtime routines, and tried behavior charts. Every specialist handled one piece, but no one had connected them all together.

When we look at a child like Owen, we see one root with many branches, and that root is very often the immune system.

A child’s gut microbiome builds itself over the first few years of life. The bacteria that settle in during this window help train the immune system, digest food, produce nutrients, and communicate with the brain. Mycotoxins can damage the gut lining and throw that microbial community off balance during the exact years it’s being built. From there, the branches start to grow.

Since so much of the immune system lives in the gut, a disrupted gut often means a child who catches everything and has a hard time shaking it. Antibiotics are sometimes necessary, but each round further disrupts the microbiome, which can set the stage for the next infection. That’s the cycle so many families get stuck in.

The picky eating isn’t stubbornness. Kids with gut issues often gravitate toward bland, beige, easy-to-digest foods because their bodies are trying to protect themselves. Meanwhile, a gut that isn’t absorbing nutrients well can’t fully fuel growth, which is how a child slowly falls off their curve.

Then there’s the gut-brain connection. The gut and brain are in constant conversation, and when the gut is inflamed, that conversation changes. It shows up as restless sleep, shorter fuses, and trouble focusing. Owen wasn’t a difficult kid. He was a kid whose body was overwhelmed.

Ear infections, strep, picky eating, slow growth, poor sleep, and big emotions can look like six separate problems. Often, they’re one.

What Mold Looks Like for Kids

Kids rarely say, “I feel inflamed.” Their bodies show it in other ways, and those signs often look nothing like what an adult with the same exposure would notice.

In the nose and lungs, it can look like a child who’s always congested, breathes through their mouth, snores, or has a lingering cough at night long after a cold has passed. Frequent nosebleeds and dark circles under the eyes that don’t fade with sleep often fit into this picture, too.

On the skin, watch for eczema that keeps returning to the cheeks, wrists, and creases of the elbows and knees or a diaper rash that won’t clear no matter which cream you try. When steroids don’t work or the rash returns after steroid use, this is another sign we’re dealing with a fungal issue internally.

In the gut, it might sound like “my tummy hurts” most days. It can also look like bloating, constipation, loose stools, a shrinking list of accepted foods, or a child who’s slowly dropping on the growth chart.

Sleep and behavior tell the story too. Night waking, night sweats, bedwetting after a child has been potty trained, meltdowns that seem bigger than the moment, trouble focusing, sensitivity to light and sound, or headaches in a child who’s young for them. Some kids even lose ground on skills they’d already mastered.

Any one of these can have many causes. When several show up together, especially in the child who’s the only one struggling, the child who’s struggled since birth, or the child who’s better away from home and worse when you’re back, it’s worth asking whether the environment is part of the story.

What Ellie’s Family Found

Once mold showed up in Ellie’s testing, her parents brought in a mold inspector. There was nothing visible anywhere in the house. But behind the wall Ellie’s nursery shared with the upstairs bathroom, the inspector found significant growth from a shower valve that had been slowly leaking for years.

Ellie’s crib was pushed right up against that wall. Her parents’ bedroom was on the other side of the house. Her brother had moved to a big-kid room downstairs before she was born. She’d been spending 12 or more hours a day everyday inches from the source.

That’s why she was the only one.

Once the wall was remediated, we were able to gently support her gut, her skin, and her body’s ability to clear what she’d been carrying. They cleaned all of her bedding and clothes with EC3 Laundry Additive and her toys with EC3 Mold Spray to decontaminate them following remediation. Over the following months her skin began to calm. Today she’s two, sleeping through the night, and eating eggs again. Her mom told us the hardest part was realizing how long they would have kept looking in the wrong places.

Ellie wasn’t the weak link in her family. She was the canary. Her body gave the whole family information they needed and her parents listened. That means she’s not only feeling better now, but also that her immune system can finish developing without a constant toxic load pushing it off course, giving her a stronger foundation for the years ahead and a better chance of avoiding the immune imbalances that can later show up as autoimmunity or fertility challenges. If your child is the one reacting, their symptoms may be trying to tell you something, too.

Work With Us

At Always Growing Wellness, our pediatric practitioners specialize in gut and skin health for children, including environmental factors like mold that so often sit underneath chronic eczema, allergies, frequent illness, and more. We work virtually with families so you can get support wherever you are. If your child’s story sounds familiar, we’d love to help you find the root. If you’d rather start learning at home, my book, Eczema Ends Here, walks parents through the root causes of childhood eczema, from gut health to the environmental toxins that are so often overlooked.