5 More Surprising Symptoms That Could Be Caused by Mold Exposure

June 4, 2025 |

When people think of mold exposure, the first things that come to mind are often sneezing, coughing, and itchy eyes. But mold can do far more damage than triggering a runny nose. In fact, mold exposure can produce a wide range of symptoms that are often mistaken for unrelated health problems.

We’ve had already talked of the common signs of mold exposure—like respiratory issues, fatigue, and skin rashes—this blog post dives deeper. Here are five more symptoms that could be caused by hidden mold in your home, office, or anywhere you spend a significant amount of time.

1. Digestive Issues

It may surprise you, but mold exposure can cause or worsen gastrointestinal problems. People experiencing chronic bloating, stomach cramps, diarrhea, or nausea—without any clear explanation—may actually be reacting to mold spores or mycotoxins (toxic substances produced by mold).

How it happens:

When mold spores are inhaled or ingested (for example, from contaminated food or air), they can irritate the lining of the digestive tract. In some people, especially those with mold sensitivity or compromised immune systems, the toxins can lead to inflammation and disrupt the normal balance of gut bacteria.

Possible signs:

Frequent indigestion or acid reflux
Unexplained nausea or vomiting
Chronic diarrhea or constipation
Food sensitivities that seem to appear out of nowhere

If you’ve seen a doctor and ruled out infections or IBS, consider checking your environment for hidden mold.

2. Mood Swings and Anxiety

Mental health symptoms like anxiety, mood swings, and even depression can sometimes be traced back to mold exposure. While this might sound far-fetched, science supports a growing link between indoor air quality and brain function.

Why mold affects your mood:

Mold spores and their byproducts can trigger inflammation in the brain and nervous system. Mycotoxins can interfere with neurotransmitters like serotonin and dopamine—chemicals responsible for regulating mood, sleep, and focus. Additionally, chronic exposure can lead to sleep disturbances and fatigue, which in turn contribute to irritability and anxiety.

You might notice:

Sudden onset of anxiety or panic attacks
Irritability or anger outbursts
Brain fog, poor memory, or trouble concentrating
Feelings of sadness or hopelessness

If emotional swings or unexplained anxiety started after a move or renovation, mold could be a hidden factor.

3. Joint Pain and Muscle Aches

If you’re feeling stiff, sore, or achy without having exercised or injured yourself, mold may be part of the problem. Many people report symptoms that mimic fibromyalgia or arthritis when they’re exposed to moldy environments for extended periods.

The mold-pain connection:

Mold can provoke an inflammatory response in the body. In people with mold sensitivity or mold-related illness (often called Chronic Inflammatory Response Syndrome, or CIRS), the immune system stays on high alert. This can lead to persistent pain, stiffness, or swelling in muscles and joints—even if there’s no underlying injury.

Common complaints include:

Morning stiffness that eases during the day
Pain in knees, shoulders, or back
Muscle fatigue or weakness
Generalized body aches with no clear cause

Don’t ignore chronic pain. If traditional treatments aren’t working, it’s worth checking your home for mold.

4. Frequent Urination and Bladder Irritation

Another unexpected symptom of mold exposure? Bladder issues. Some individuals report frequent urination, urgency, or a burning sensation that mimics a urinary tract infection (UTI)—yet tests come back negative.

What’s going on?

Mold-related toxins can cause systemic inflammation that irritates the bladder lining, leading to symptoms similar to interstitial cystitis or other bladder disorders. This condition may be more common in women, though men can be affected as well.

Symptoms to look for:

Urge to urinate frequently, even without drinking a lot
Pain or pressure in the bladder area
Feeling like your bladder is never fully empty
Negative tests for bacteria or infection

If your bladder problems seem unresponsive to standard treatment, consider environmental toxins like mold as a potential trigger.

5. Light Sensitivity and Vision Changes

People rarely associate vision problems with mold, but some individuals with mold exposure report light sensitivity, blurred vision, and even eye pain. These symptoms can be especially confusing because they don’t always coincide with traditional allergy symptoms like red, itchy eyes.

Why vision may be affected:

Some molds produce neurotoxic compounds that can affect cranial nerves, including those connected to vision. Inflammation triggered by mold can also affect the optic nerve or other structures in the eye, especially in sensitive individuals. This is more common in those with CIRS or mold-related neurological symptoms.

You may notice:

Difficulty adjusting to bright light
Blurry vision or visual “floaters”
Eye pressure or aching behind the eyes
Sensitivity to screens or fluorescent lighting

If your eye doctor can’t explain the problem, it’s worth looking at your environment—especially if you have other unexplained health issues.

If you recognize any of these symptoms in yourself or a loved one, don’t panic—but don’t ignore them either. Mold-related illness can be complex, but recovery is possible.

Final Thoughts

Mold doesn’t just live in your walls or under your sink—it can live in your body through the symptoms it creates. If you’ve been dealing with odd, chronic health issues and haven’t found answers, don’t overlook the possibility that mold could be affecting you in unexpected ways.

Understanding the full range of symptoms gives you the power to take back control of your health—and your home.

We are MoldBusters New Mexico, and there is no job we can’t do!