Wellness

What Is Gluten Cross-Reactivity?

What Is Gluten Cross-Reactivity?

What Is Gluten
Cross-Reactivity?

Vikki Petersen

Functional medicine practitioner Vikki Petersen explains what gluten cross-reactive foods are, how she believes they affect her patients, and how she’s helped people with celiac disease (and nonceliac gluten sensitivity) fully recover.


A Closer Look at Gluten Sensitivity

Years ago, a patient came to me with tears of exhaustion. After her diagnosis with celiac disease, she was committed to eating gluten-free. She had spent the last six months dedicated to a strict gluten-free diet—buying certified gluten-free foods, mostly eating at home, preparing food for outings, etc. But that wasn’t why she was exhausted. Her exhaustion came from the fact that, despite all her efforts, she was experiencing symptoms of celiac disease, even on a gluten-free diet. Some of her nonglutenous foods were triggering her celiac symptoms, and she couldn’t figure out which ones and why. She thought she was hallucinating and becoming paranoid.

But she was not. And she was not alone. Throughout my thirty years of practice, many patients have come into my office with celiac disease. They’ve stopped eating gluten, but when they eat certain foods their bodies react as if they did—with symptoms of bloating, brain fog, insomnia, depression, anxiety, headaches, etc.

Gluten Cross-Reactive Foods

We eventually figured out what was going on—they were eating gluten cross-reactive foods. Let me explain.

With celiac disease, gluten proteins (gliadins and glutenins) are seen by the immune system as harmful to the body. So the body destroys gluten proteins and, in the process, the lining of the small intestine where they are found. In these patients, the immune system was responding to nongluten proteins in a similar way, which should not happen. Yet it was. What we think is happening is that their immune systems were mistaking nongluten proteins—like proteins in corn, milk, soy, rice, white potatoes, quinoa, eggs—for gluten proteins because of their similar structures. So it was destroying these nongluten proteins as if they were gluten proteins. We call this gluten cross-reactivity. And we call the foods that the immune system mistakes for glutenous foods cross-reactive foods.

The immune system does this because it’s extremely overworked due to so many years, sometimes decades, of gluten exposure. It may seem as if just removing gluten foods would be enough to allow the gut to return to a healthy state, but prior to being diagnosed with celiac disease, most people eating a typical American diet are likely eating gluten several times daily. With celiac disease, this is a consistent demand on the immune system, without rest. It’s like going to work without sleep or food for an extended period. If you’re not able to rest or get proper fuel, you’re more likely to make errors that you wouldn’t normally make if you are rested and properly fueled. Just as the entire body does, the immune system needs proper time and care to recover completely.

Healing Gluten Cross-Reactivity

In the past, if we suspected a patient was experiencing gluten cross-reactivity, in addition to having them eating gluten-free, we would remove from their diet nearly twenty cross-reactive foods (foods that we found patients with celiac disease to be sensitive to) and slowly reintroduce each one to determine which foods they were sensitive to. The process was more cumbersome than we liked. But now, in our practice, we’ve found that if we use multi-tissue antibody testing (from Cyrex Laboratories)—although it’s not widely used by the medical profession—we can test a patient’s reactivity to all the gluten cross-reactive foods. This allows us to better determine which foods our patients should avoid during the gut-recovery period. We remove only those foods (for about three months) and provide a gut-healing protocol. With these steps, we see our patients’ guts completely recover, and cross-reactive foods can be safely reintroduced.

Gluten Cross-Reactive Foods

Petersen has found that her patients with celiac disease (and nonceliac gluten sensitivity) are sometimes sensitive to the foods below.

  1. instant coffee

  2. cow’s milk

  3. whey protein

  4. oats

  5. yeast

  6. millet

  7. corn

  8. rice

  9. sesame

  10. buckwheat

  11. sorghum

  12. hemp

  13. amaranth

  14. quinoa

  15. tapioca

  16. teff

  17. potato

  18. soy

  19. egg

Diagnosing Celiac Disease Earlier

Cross-reactivity is just one of the many conditions that may be associated with celiac disease. Other health conditions can include thyroid disease, liver disease, lymphoma, osteoporosis, memory loss, depression, anxiety, and mood swings. Diagnosing celiac disease as early as possible may help reduce the number of patients who experience these and other conditions. One way to do that is by diagnosing celiac disease before the lining of the small intestine is severely damaged, which is currently required for celiac disease to be diagnosed.

What I mean by that is, normally, the tiny fingerlike projections (called villi) that line the small intestine provide a very large surface area for nutrients to be absorbed through. With celiac disease, these villi erode over time with gluten exposure. And in the most severe cases, they are completely flattened, causing a dangerously low level of nutrient absorption and subsequent health conditions. Currently, to be diagnosed with celiac disease requires, along with blood tests, the villi of the small intestine to be flattened—severely damaged. Prior to developing severely damaged villi, few people are being diagnosed with celiac disease, even though they potentially have it.

What typically happens is that doctors use the Marsh classification system to analyze the villi to diagnose celiac disease. It includes a ranking scale from 0 to 4; 0 represents the presence of normal villi and 4 represents severely damaged villi. Patients with a 3 or 4 ranking can be diagnosed with celiac disease, but patients with a ranking of 1 or 2 are generally not, despite their blood tests showing a possibility of them having the disease.

Yet the Marsh scale classification system was not originally intended to be a diagnostic tool for celiac disease but rather a system to show the progression of celiac disease and to help ensure that it’s diagnosed prior to the villi being severely damaged. But because the Marsh scale is not used in the way it was intended, there are potentially many people with celiac disease who are undiagnosed. The standard diagnostic process is evolving, but in the meantime, if you or someone you know suspects they have celiac disease, consulting an experienced celiac disease expert is best.


A pioneer of the gluten-sensitivity movement, Vikki Petersen—doctor of chiropractic, certified clinical nutritionist, and certified functional medicine practitioner—has been endorsed by the National Foundation for Celiac Awareness and the Gluten Intolerance Group of North America for her contributions to gluten awareness in the US. She is a coauthor of The Gluten Effect and Hiatal Hernia Syndrome and founder and executive director of the Root Cause Medical Clinics, where she currently practices.


This article is for informational purposes only. It is not, nor is it intended to be, a substitute for professional medical advice, diagnosis, or treatment and should never be relied upon for specific medical advice. To the extent that this article features the advice of physicians or medical practitioners, the views expressed are the views of the cited expert and do not necessarily represent the views of goop.


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