You've Heard of Gluten...But What About Gliadin?
If you’ve been diagnosed with celiac disease or have a food sensitivity with similar triggers, it’s likely that gluten is always on your mind. Wheat, barley and rye are quickly ruled as off-limits and fighting cross-contamination becomes a daily struggle. However – for many people with a gluten intolerance – finding GI relief is a little more complex than simply avoiding this pesky protein.
"Celiac disease is characterized by a hereditary response to gliadin – a small fraction of the gluten found in wheat, barley and rye,” says Dr. Chris Meletis, N.D. and Notch’s medical advisor.
Because gliadin is a major protein component of gluten and can cause intestinal stress, gliadin and gluten sensitivities often go hand-in-hand.
"It really comes down to awareness,” Meletis says. “Most people don’t know what gliadin is or what food it’s in.”
Though numerous studies have acknowledged gliadin as a primary trigger for those with celiac disease or a non-celiac gluten sensitivity (NCGS), recent research suggests it may pose an issue for the general population as well.
As noted in this particular study, the zonulin upregulation caused by gliadin exposure can increase intestinal permeability in all individuals – not just those who are sensitive to gluten. For this reason, many researchers believe that gliadin may play a crucial role in the development of GI conditions such as irritable bowel syndrome (IBS) and leaky gut.
“I encourage my patients to be as informed as they can when it comes to hidden sources of gluten and gliadin,” Meletis says.
What exactly is gliadin?
The term “gliadin” actually encompasses a group of glycoproteins found within wheat and other gluten-containing grains. Gluten proteins are generally divided into two groups: soluble gliadins and insoluble glutenins. Because gliadin is a major component of gluten, people with celiac or Crohn’s disease are often sensitive to gliadin as well.
If a food is gluten-free, does that mean that it’s gliadin-free as well?
Not exactly. Because gliadin is a component of gluten, foods that contain gluten will inevitably have gliadin. However, this doesn’t necessarily work both ways. Some grains, such as oats, may contain gliadin even though they are generally considered “gluten-free.” Both the National Institutes of Health and the Gluten Intolerance Group suggest avoiding oats when pursuing a gluten-free diet. Several studies also suggest that oats may elicit a similar antibody response in those with celiac disease.
“There is still some controversy surrounding gliadin and oat reactivity,” Meletis says. “I simply tell my patients that it’s best not to assume the term ‘gluten-free’ on a package of oats means it’s safe to consume.”
How do you diagnose a gliadin sensitivity?
While research on gliadin has grown in recent years, there still aren’t many published studies on the prevalence of gliadin sensitivities. According to a report from Notch’s lab partner that encompasses all the food sensitivity tests completed in 2020, gliadin was the second most reactive allergen in the grain group, ranking above both gluten and oats.
As of now, the primary way to diagnose a gliadin sensitivity is by taking a food sensitivity test. Most of Notch’s IgG food sensitivity panels test for gliadin, making them a great place to start.
“Notch’s lab partner has performed hundreds of thousands of food sensitivity tests,” Meletis says. “The fact that gliadin is the second most reactive grain antigen just shows how vital it is to measure gliadin in addition to gluten.”
What is the best way to avoid foods with gliadin?
One of the simplest ways to avoid gliadin is to adhere to a gluten-free diet and be wary of other foods that may contain gliadin. However, before eliminating any specific foods, it’s best to consult with your doctor or dietitian and get their recommendations on how to proceed. In general, we suggest starting with a food sensitivity test, sharing your results with your healthcare provider and – with their guidance – coming up with an elimination diet or alternative solution that may suit your needs.
In summary, if you’re following a gluten-free diet, make sure you’re taking gliadin into consideration as well.
“There's a reason conventional medicine tests for anti-gliadin antibodies in celiac patients,” Meletis says. “If you are going gluten-free, make sure you are both gluten and gliadin-free.”