Digestive Health Mold Illness

How on earth can mold cause gluten intolerance?

By Kim Crawford, M.D. Last updated: September 6, 2018
can mold cause gluten intolerance

The crazy way mold impacts your gut:

For those of you who think you have gluten sensitivity and have come across this article, wondering “how can mold cause gluten intolerance?” just wait. In this article, I will prove to you that gluten intolerance can be the first and sometimes the only sign of continuous toxic mold exposure. How does this happen? Mold toxins are inhaled or ingested and find their way down to the GI tract where they make the gut more permeable to various proteins.

Current research bears out that gluten is the first gut-noxious substance that is readily identified. This is the first step in the sequence of toxic mold causing gluten sensitivity. Speaking of which, let’s start with a quick introduction to gluten intolerance. If you are reading this, you might be questioning whether or not you have gluten intolerance. Perhaps, you want to know what is the difference between gluten intolerance and celiac disease. Further, you might be wondering if the mold in your home or office is “the problem.” I’ll get to it all.

What is gluten intolerance?

First, let me roughly outline the difference between being “gluten intolerant” and having celiac disease. By the way, toxic mold can cause all sorts of auto-immune disease, including celiac disease. This is a complex topic and I will write about it on this blog soon. Meanwhile, just be in touch with me if you think this is your problem. Now back to celiac versus gluten intolerance.

Classic celiac disease symptoms include diarrhea, abdominal pain, and weight loss. If you have gluten intolerance, you generally have less severe GI symptoms. However, some people with celiac have no GI tract symptoms, and the same holds true for those with gluten intolerance.

can mold cause gluten intoleranceEither group (true celiacs or gluten-intolerant people) can have a little bloating and even constipation, but can also have a history of food allergies, leaky gut, and skin rashes following the ingestion of gluten.

This holds true for mold toxin sufferers, but most commonly they report GI symptoms if they have gluten issues due to mold toxins (mycotoxins).

Now, if the mold illness progresses untreated for years, mold toxin gut impact can evolve into full-blown auto-immune GI tract disease (Crohn’s) or full blown leaky gut.

This article is not addressing those cases.

Here, I’m talking about those of you who are experiencing symptoms and might have heard that mold could be the cause. There are laboratory tests that will help to differentiate what is going on. I’ll get right to that after a minor warning.


If you suspect you might have a gluten issue, do not simply cut gluten from your diet. Why? The answer is you will have falsely negative lab testing if you don’t have gluten “on board” when doing bloodwork. The labs you need are as follows:

Gluten intolerance versus celiac disease with some mold thrown in:

Anti-tissue transglutaminase (tTG-IgA):

This is the screening test for “all things gluten.” It is the most sensitive test for celiac disease. Approximately 98% of people with celiac (mycotoxin or non-mycotoxin-caused) will have a positive tTG test. False positives can be found in people who have other auto-immune diseases such as Rheumatoid arthritis and Type I diabetes. Yes, you are reading correctly—if you have celiac either caused or not caused by mycotoxins, this will be positive the vast majority of the time. Results may sometimes be negative, and that doesn’t mean you are not having gluten issues. I’ll explain how to determine with more certainty which category you fall into after I list the next three tests.

Anti-endomysial antibodies (EMA-IgA):

If you have an elevated EMA, you have close to a 100% chance of having celiac disease. Again, mycotoxin or non-mycotoxin caused. However, this test is not as sensitive as the tTG test. So, approximately 5-10% of people with celiac disease have a negative EMA test.

Anti-gliadin antibodies:

These antibodies are the “gold standard” when we are looking for gluten issues in mycotoxin illness. They are present the vast majority of the time that someone has a “gluten sensitivity problem” and indicate that the body is making antibodies to the protein in gluten called gliadin. They can also be present in non-mycotoxin illness. So, how do we tell the difference between all of these things? How do we know if mold is the root cause problem?

HLA testing:

This isn’t as complicated as you might think. We are all taught that the only real way to diagnose celiac disease is with a small intestinal biopsy. Yes, that is the “scientific way”  to go which is touted by all of the GI studies on celiac disease. We want to diagnose “real celiacs” because the gliadin permeates the blood-brain barrier, causing actual damage to brain cells. That’s the primary reason. Of course, there are secondary reasons, but to me, that’s the important reason. However, this won’t tell us if toxic mold is the cause.

That’s where HLA (genetic) testing comes in. While we are not “supposed” to use HLA testing as diagnostic, it sure can be highly suggestive when it comes to ruling out mold or ruling out celiac. Genetic testing is helpful to rule out true celiac disease but is not as conclusive as we’d like. 30% of Caucasians are positive for one of the two “celiac genes.” That common gene is the HLA-DQ-2 gene. The other is the less common HLA-DQ-8 gene. If you have both of these and have “the symptoms” as well as positive testing on your EMA, you are quite likely to have non-mycotoxin celiac disease.

If you don’t have these HLA positives but have symptoms as noted at the beginning of this article, you are now left wondering about gluten sensitivity and involvement of toxic mold. You will have the positive anti-gliadin antibodies if you have toxic mold involvement. These might be positive and might be negative with non-mycotoxin gluten sensitivity. To nail down the mycotoxin diagnosis even more, when you have bloodwork for the celiac HLA tests you want to request HLA testing that will identify if you are genetically susceptible to mycotoxin illness.

HLA testing for mycotoxin sensitivity:

You want to have your doctor order the following tests. DRB1,3,4,5, and DQB1. Your doctor will not be familiar with this so just ask for these specifically, and his staff can look them up. The Celiac testing is called DQ2 and DQ8 testing; this is fairly common, and your doctor will be tempted to order these tests so check with him/her.

When the HLA tests come back, your doctor will need help interpreting them. I suggest using Labcorp, as they have very reliable HLA testing assays and will provide your doctor with excellent scientific help to interpret the meaning of your HLA profile.

It has been shown in many studies in patients with CIRS (biotoxin-mostly mold toxin illness) and even Type 3 Alzheimer’s disease where mold can cause Alzheimer’s, that genes play a major role in illness. Studies reveal about 24% of the population cannot clear toxins such as mycotoxins via their regular immune system and, instead, dysfunctionally activate their innate immune system to cause all sorts of issues including the common one we’re discussing in this article.

Here are the susceptible HLA types:

DRB1: 7,13,17,18

DQ: 2, 3, 6, 2/3, 4

DRB3: 52A, B, C and 52A

DRB4: 53 AKA 7253

DRB5: 51

This will be “Greek” to most of you and to most of your doctors. If you have a mold-susceptible or multi-susceptible (not listed) haplotype (one gene) and have gluten symptoms with or without positive laboratory testing, then I suggest that you look for mold.

Searching for the culprits: Mold toxins can cause gluten intolerance

It is estimated that up to 50% of U.S. buildings have water damage of some sort. Un-addressed water damage can turn into mold within 48 hours. Mold requires food (drywall) and water. Increasingly, indoor molds are toxin-producing molds. We no longer assume that homes or offices harboring molds and mold toxins smell “musty.” In fact, the opposite is true. The first thing you can do is to inspect your attic for HVAC duct leaks. Then, inspect around pipes leading to showers, toilets, etc. If you find mold, and even if you don’t find mold, the next step is easy. You need an ERMI (genetic sampling of the dust which will contain mold spores and fragments) throughout the suspected area. The company Mycometrics will send you a test kit and help you evaluate the results.

Treating your gluten issue:

You must have your GI tract evaluated by an expert who can tell you your correct diagnosis, including whether or not you have progressed symptomatically to have a leaky gut. If you only have a gluten issue, you must avoid eating gluten. This is a very strict rule for everyone with any sort of gluten problem. We are becoming increasingly aware that gluten might be a “problem” for everyone, so at this juncture, I am quite wary of gluten in general. “When in doubt, cut it out.” Gluten might injure not just GI mucosa (meaning most of your immune system) but brain cells, too. The research is truly looking as if just about everyone will benefit from avoiding grains.

Grains cause spikes in insulin, leading to fat storage and obesity. Furthermore, studies link high-carb diets with everything metabolically “bad.” We’re talking type 2 diabetes, high cholesterol, high blood pressure and even cancer. There is a rather strong ongoing study about the relationship between grains and Alzheimer’s. At any rate, here is an article on the dangers of not eating a gluten-free diet with guidelines of how to eat gluten free. And here is an article about how to do nutritional ketosis.

The “bright side” of having a mycotoxin illness, even if you have positive anti-gliadin antibodies, is that, with treatment, the antibodies and therefore the symptoms to gluten often will reverse. However, it is reported that once a CIRS patient has a gluten issue, they will usually feel much better avoiding gluten for life. I’m doing it, and I don’t miss it one bit. If this turns out to be you, you won’t either.


  1. Dr. Kim-I have both “celiac genes” positive but have also been diagnosed with CIRS from toxic mold. Are you saying that when my CIRS clears up that there is a chance I could have that positivity reversed and therefore be able to eat gluten again?Thanks for your answer when you can, Susan.

    • Hi Susan,
      If you have true celiac positivity with the auto-antibodies, the 2 HLA haplotypes and a positive biopsy, then even if mold triggered the gut permeability that led to your intitial symptoms, you have celiac disease and that will not be reversed by treating the CIRS-leaky gut and so on. You will always need to avoid gluten. But you know what-we are learning more and more about how toxic gluten likely is for everyone so I recommend that people (at a minimum) drastically reduce their gluten consumption ANYWAY and ideally (what I do) I recommend that they avoid gluten products. So you just need to get used to eating this way. It’s a bit dicey at first but will become second nature to you as it is to me. Lot of great info is found at celiac dot com.

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