Foods to Avoid: What Foods Are High in Gliadin?

November 17, 2025 •

4 min read

According to a 2013 study, approximately 30% of US adults were trying to reduce or eliminate gluten from their diet, highlighting the need for awareness around gluten components like gliadin. So, what foods are high in gliadin? This comprehensive guide explains gliadin's role in gluten and identifies specific foods that contain high levels of this protein.

Quick Summary

A detailed look at foods containing high levels of gliadin, a key protein in gluten. The guide explains where to find gliadin and its impact on gluten-sensitive individuals, outlining which grains and processed items are the biggest sources.

Key Points

Gliadin is a key protein in gluten: It is found in grains like wheat, rye, and barley, triggering reactions in sensitive individuals.
Wheat is the primary source: All forms of wheat, including spelt, durum, and kamut, contain high levels of gliadin.
Hidden gliadin is common: Watch for gliadin in processed foods, thickeners, sauces, and flavorings.
Beer and malt are major sources: The brewing process often uses malted barley, making beer high in gliadin.
Oats can be risky: While pure oats are gliadin-free, they are frequently cross-contaminated with gluten unless certified otherwise.
A gluten-free diet is a low-gliadin diet: Adhering to a strict gluten-free diet is the most effective way to eliminate gliadin intake.

Understanding Gliadin and Gluten

Before identifying foods high in gliadin, it's essential to understand its relationship with gluten. Gliadin is one of the two primary protein components of gluten, alongside glutenin. When flour from grains like wheat is mixed with water, gliadin and glutenin form a sticky, elastic network that gives dough its chewy texture and allows bread to rise. For individuals with celiac disease or non-celiac gluten sensitivity, gliadin is the protein primarily responsible for triggering an adverse immune response.

The Main Sources of Gliadin

The most direct sources of gliadin are the grains that contain gluten. Therefore, any food made from these grains will be high in gliadin. While wheat is the most common and potent source, gliadin-like proteins, known as prolamins, are also found in other related cereals.

Wheat: The most prominent source. All varieties of wheat, including durum, spelt, farro, and kamut, are high in gliadin.
Rye: Contains secalins, which are structurally and functionally similar to gliadin and can trigger a similar immune response.
Barley: Contains hordeins, another group of prolamins that act similarly to gliadin and are problematic for those with sensitivities.
Triticale: A hybrid grain of wheat and rye, meaning it contains high levels of gliadin and secalins.

Obvious and Hidden Foods High in Gliadin

While whole grains are the most apparent source, gliadin can be hidden in many processed foods. Reading labels carefully is crucial for anyone managing a gluten-free diet.

Common Foods High in Gliadin

Breads and Baked Goods: This includes bread, pastries, cakes, cookies, and other baked goods made with wheat flour.
Pasta and Noodles: Most traditional pastas and noodles are made from wheat (durum) and are major sources.
Cereals: Breakfast cereals, especially those containing wheat or barley, as well as malt, which is derived from barley, should be avoided.
Beer: Malt is a key ingredient in beer, making most beers high in gliadin and gluten.
Crackers and Bars: Many snack crackers, granola bars, and protein bars are made with wheat flour or other gluten-containing ingredients.
Soups and Sauces: Wheat flour is a common thickener in canned soups, gravies, and sauces.
Meat Analogues: Vegetarian or vegan meat substitutes often use wheat gluten as a protein base and binder.

Less Obvious Sources of Gliadin

Malt: A flavoring often derived from barley and used in candies, flavorings, and various beverages.
Hydrolyzed Vegetable Protein (HVP): Can be a hidden source if derived from wheat, used as a flavor enhancer.
Starch and Thickeners: Some food starches and thickeners use wheat as a base.
Processed Meats: Certain processed lunch meats, hot dogs, and sausages may use binders or fillers derived from wheat.
Dressings and Marinades: Some sauces and marinades use wheat flour as a thickener or contain other gluten-based components.

Gluten-Containing Grains vs. Gluten-Free Alternatives

To help navigate dietary choices, here is a comparison of common grains and their gliadin content.


Feature	Gluten-Containing Grains (High Gliadin)	Gluten-Free Grains (No Gliadin)
Common Examples	Wheat, Rye, Barley, Spelt, Kamut	Rice, Quinoa, Corn, Buckwheat, Millet, Teff
Gliadin Content	High	None
Use in Baking	Provides elasticity and structure; necessary for traditional bread baking.	Requires binders (e.g., xanthan gum) for structure; can be dense or crumbly.
Protein Structure	Contains gliadin and glutenin, forming a gluten network.	Proteins are not gliadin/glutenin and do not form a gluten network.
Dietary Suitability	Unsuitable for individuals with celiac disease or non-celiac gluten sensitivity.	Suitable for those on a gluten-free diet.
Other Considerations	Malt and other derivatives are also gliadin sources.	Oats are often cross-contaminated and require certified gluten-free labels.

Navigating a Low-Gliadin Diet

Following a low-gliadin diet means adhering to a strict gluten-free regimen. This involves more than simply avoiding bread. Individuals must be vigilant about hidden sources in processed foods, condiments, and even cross-contamination. Always read food labels carefully, looking for wheat, barley, rye, spelt, or malt. For those with celiac disease, certified gluten-free products are the safest option, as they are tested to ensure they are free of cross-contamination. Consulting a healthcare professional or registered dietitian is highly recommended for creating a safe and nutritious meal plan tailored to specific needs.

The Role of Oats

The role of oats in a gliadin-sensitive diet is a common point of confusion. Oats do not contain gliadin, but they do contain a similar protein called avenin. While most individuals with celiac disease can tolerate pure, uncontaminated oats, there is a risk. Many commercially available oats are processed in facilities that also handle wheat, barley, or rye, leading to cross-contamination. Therefore, experts advise that individuals with severe sensitivities only consume oats certified and labeled as gluten-free.

Conclusion

Foods high in gliadin are those containing gluten, primarily found in wheat, rye, and barley. This includes obvious culprits like bread and pasta, as well as numerous hidden sources in processed items, sauces, and beverages. For individuals with gluten-related disorders like celiac disease, avoiding these foods is critical for managing symptoms and maintaining health. Understanding the differences between gluten-containing and gluten-free grains empowers people to make informed dietary choices, with a special consideration for the potential risks of cross-contamination in products like oats.

Frequently Asked Questions

No, gliadin is one of the two main protein components that make up gluten. Gluten is the broader term for the family of proteins, while gliadin is the specific part that causes most of the adverse immune reactions in people with celiac disease.

When a person with celiac disease consumes gliadin, it triggers an immune response that damages the lining of the small intestine. This can lead to symptoms like malabsorption of nutrients and various gastrointestinal issues.

Yes, all varieties of wheat, including ancient grains like spelt and kamut, are sources of gliadin. While the exact amount may vary, all wheat-based products should be considered high in gliadin.

Yes, gliadin can be present in non-food items, although this is less common. It might be found in some cosmetics, medications, or supplements. For individuals with severe sensitivity, it's important to check the ingredients of all products, not just food.

To avoid hidden gliadin, always read the ingredient labels carefully. Look for terms like 'wheat,' 'barley,' 'rye,' 'malt,' and 'hydrolyzed vegetable protein' (HVP). Choosing certified gluten-free products is the safest bet to ensure no gliadin is present due to cross-contamination.

Yes, gliadin is specific to wheat. However, similar proteins called prolamins exist in other gluten-containing grains. Rye contains secalins, and barley contains hordeins. These proteins have similar properties to gliadin and can cause issues for those with gluten sensitivities.

Malt is typically made from barley, a grain that contains gluten proteins similar to gliadin. It's often used as a sweetener or flavoring in various foods and beverages. Its presence means the product is not gluten-free and should be avoided by those with gliadin sensitivity.