If you have celiac disease and have said goodbye to gluten, yet you’re still experiencing symptoms, you may have what is called gluten cross reactivity. In this article, I define gluten cross reactivity, list what foods are most susceptible to cross reactivity, and discuss how you can determine if you’re having a reaction. This article is not a substitute for medical advice. This post may contain affiliate links. Please see my disclosures and disclaimers.
A subgroup (about 30 percent) of patients with celiac disease following a strict gluten-free diet report still experiencing symptoms similar to gluten exposure. These symptoms include bloating, gas, diarrhea, constipation, brain fog, fatigue, joint pain and more. Why is this?
In some cases, it means the celiac disease patient is experiencing a phenomenon called gluten cross reactivity. This occurs when the body thinks the person is eating gluten, a protein found in wheat, barley, rye and sometimes oats, even though they are following a strict gluten-free diet.
Patients with celiac disease produce anti-α-gliadin and anti-tTG antibodies, which are detectable in standard blood tests that test for celiac disease. These antibodies are only present in people with confirmed celiac disease and not in patients with non-celiac gluten sensitivity.
When someone with celiac disease eats gluten, his or her cells produce antibodies that attack gluten and the healthy tissue surrounding the lining of the small intestine. The celiac patient’s immune system will mark gluten as a foreign invader and goes into attack mode every time the protein is present.
Please note that people with non-celiac gluten sensitivity or a gluten intolerance test negative for the auto-antibodies found in people with celiac disease. Therefore, someone with gluten sensitivity does not experience gluten cross reactivity. Only people with celiac disease may experience a reaction.
Gluten Cross Reactive Foods List
Gluten cross reactivity can happen with many foods, but the 2017 study on cross-reactive foods by researchers Aristo Vodjani and Igal Tarash found that the following foods can become confused for gluten by the body’s immune system:
- Dairy (cow’s milk, milk chocolate, milk butyrophilin, whey protein, casein)
- Instant Coffee
- Yeast (brewers and bakers)
Other foods were tested in the study, but did not exhibit gluten cross reactivity.
Researchers said, “In this study, we identified antigens and peptides from milk, yeast, millet, corn, rice, oats and tissues that strongly reacted with … antibodies produced against gliadin. The reactivity between gliadin peptides and various food antigens are pathogenetically relevant because if the presence of these cross-reactive substances are left untreated, an individual may develop multiple autoimmune reactivities.”
The researchers went on to conclude that if celiac patients following a gluten-free diet do not show symptom improvement, they may need to potentially eliminate cross-reactive foods.
The researchers add, “The present study supports the hypothesis that if the high prevalence of antibodies against dietary proteins and peptides and their cross-reaction with various tissue antigens are not taken seriously, and if proper measures are not implemented, the result may be the development of autoimmunity in the future.”
How to Identify Foods Causing Gluten Cross Reactivity?
If you suspect your body is reacting to a non-gluten protein in a similar way it would react to gluten, consider getting tested and/or implementing an elimination diet to see if this rare phenomenon is impacting you.
1) Take a Gluten Cross Reactive Blood Test
The Cyrex Array 4 test – also called the Gluten-Associated Cross-Reactive Foods and Foods Sensitivity – test can be a first step in identifying potential foods causing gluten-cross reactivity.
The test will look for potential cross reactivity with the six foods listed above – corn, dairy, millet, oats, rice and yeast – via an IgG panel.
It will also check for cross reactivity to foods that are newly introduced or over consumed when following a the gluten-free diet (foods not typically consumed outside the GF diet), including amaranth, buckwheat, hemp, potato, sesame, sorghum, tapioca, teff and quinoa.
The test also checks for a reaction to egg and soy, which Cyrex claims are common “antigenic” foods.
Please keep in mind that the testing provided by Cyrex Laboratories requires an order by a licensed healthcare professional and the Cyrex Array 4 test is best suited for people with celiac disease.
2) Implement an Elimination Diet
Alternatively, if you decide not to take the Cyrex test, you can conduct an elimination diet on your own or with a trusted health coach or health professional.
Either eliminate all suspect foods for 6 weeks, or simply eliminate one food at a time for 6 weeks before testing another one. If you eliminate all suspect foods on one day, be sure to reintroduce them individually, spacing the reintroduction of each food by at least one week.
An elimination diet may just help you pinpoint which of these suspect foods is the culprit behind your gluten-cross reactivity.
Treating Gluten Cross Reactivity
The only way to treat a gluten cross reactivity, either through a food identified through a blood test or via elimination diet (or both), is to permanently remove that food from your diet.
When you reintroduce those foods, your symptoms will emerge again as your body remembers that protein and will always want to attack it.
If Symptoms Persist
If you are still experiencing symptoms similar to your pre-gluten-free diet years, there may be something more at play here than a gluten cross reactivity.
Could You Still Be Eating Gluten?
Is your gluten-free diet really gluten free? Consider monitoring the effectiveness of your gluten-free diet, which I talk about in detail in this article. You might still be consuming gluten, and that would explain why you’re feeling how you’re feeling.
Is Your Gut Healthy?
You might have a leaky gut, and when you do, it can wreak havoc in your body, making you feel awful and compounding your symptoms.
Could You Be in Need of a Digestive Boost?
Sometimes our digestive juices can use a boost, and that is when a gluten digestive enzyme can help. Digestive enzymes, in general, aid your digestive system in properly breaking down and digesting the food you eat.
Read more about the pros and cons of gluten digestive enzymes and talk to your healthcare provider to see if they might be right for you.
Could You Have Other Food Sensitivities?
Researchers suggest that if symptoms persist despite strict elimination of gluten and gluten cross-reactive foods, “further investigation for other food intolerances should follow.”
Discuss potential food intolerances with your doctor and consider taking an at-home food sensitivity test (which is most accurate when you have taken the time to heal your gut issues first), and continue with your elimination diet to test additional suspect foods that might indicate a potential food intolerance vs. gluten cross reactivity.
The Oats-Gluten Cross Reactivity Myth Debunked
A lot of people in the celiac community perpetuate rumors about oats, most of which are unfounded claims. It may be because oats contain a protein called avenin, which is similar in structure to gluten.
In one study, researchers investigated the effect of 50 grams of oats taken daily for 12 weeks by people with celiac disease and found “no clinical or laboratory evidence of disease activation.”
(Please note that oats must be labeled gluten free and tested by the manufacturer and/or certified gluten free by a third party testing agency.)
Don’t be so quick to give up oats as they are an excellent source of soluble fiber, which is essential to your digestive health.
If you experience digestive symptoms after eating oats, it could be due to the high fiber content in oats, not gluten cross reactivity.
Know the Facts
While gluten cross reactivity is rare, people with celiac disease can still experience it. If you still experience symptoms consistent with gluten epxosure despite following a strict gluten-free diet, get tested for gluten cross reactivity or follow an elimination diet to better understand how your body reacts to different foods.