The FDA requires food manufacturers to disclose wheat on every label — but wheat is only one of three grains that harm people with celiac disease. Barley and rye also contain gluten, and neither is covered by the standard allergen warning system. That gap, documented in the FDA’s food allergies guidance on FDA.gov, is one of the most consequential things I have had to understand since my son was diagnosed.
Celiac disease and food allergies are regulated under two separate systems. Both matter for celiac families — but they protect against different things, and confusing them leads to real harm.
What This Means for You
The FDA’s allergen labeling system covers what the law calls the “Big 9” major food allergens: milk, eggs, fish, shellfish, tree nuts, peanuts, wheat, soybeans, and sesame. Wheat is on that list. When you see the allergen statement at the bottom of a nutrition panel, it reflects these nine categories only.
Celiac disease is not a food allergy. It is an autoimmune condition triggered by gluten — a protein found in wheat, barley, and rye. A product that contains no wheat can still carry enough gluten from barley or rye to cause intestinal damage in a celiac patient. No allergen warning will flag it. No “Contains:” statement will call it out.
The FDA’s separate gluten-free labeling standard is what actually protects celiac patients. Any product labeled “gluten-free” must contain fewer than 20 parts per million of gluten and must be free of wheat, barley, rye, and their derivatives. That standard applies when a manufacturer chooses to use the “gluten-free” claim — but the claim is voluntary. A product can be completely safe for celiac patients and carry no gluten-free label at all.
The practical rule is simple: look for “gluten-free” specifically. Do not rely on the absence of wheat in the allergen box. A malt vinegar (from barley), a soup with rye flour, or a breakfast cereal with barley extract can all escape the allergen statement entirely — but none of them are safe for my son.
As we covered when the FDA took steps to improve gluten ingredient disclosure, the agency has been working to make these distinctions clearer. Progress is real, but the two-system structure remains in place — and celiac families need to navigate both.
Key Takeaways
- Wheat allergen labeling is mandatory under FDA rules, but barley and rye are not covered by the allergen framework
- “Wheat-free” does not mean “gluten-free” — celiac families must look for that specific claim
- The FDA’s gluten-free standard (under 20 ppm) covers all gluten sources: wheat, barley, rye, and their derivatives
- Malt, malt extract, and malt vinegar all come from barley and contain gluten — they will not trigger a wheat allergen warning
- The gluten-free label is voluntary; safe products may carry no label, while the label itself provides regulatory assurance when present
The Science
Want to understand how this actually works? We’ll walk you through the technical details below and define every term. No medical degree required.
Two Regulatory Systems, One Kitchen
The FDA administers food allergen labeling under the Food Allergen Labeling and Consumer Protection Act (FALCPA), first passed in 2004 and expanded by the FASTER Act of 2021, which added sesame as the ninth major allergen. This framework requires that manufacturers declare any of the Big 9 allergens — prominently and in plain language — on the product label.
The mechanism behind a true food allergy is an IgE-mediated immune response: the immune system produces antibodies called immunoglobulin E that recognize a food protein as a threat and trigger a rapid reaction, ranging from hives to anaphylaxis. The allergen labeling system was designed specifically to protect people whose immune systems respond this way.
Celiac disease involves a completely different pathway. It is an autoimmune response: exposure to gluten causes the immune system to attack the lining of the small intestine itself. The damage targets villi — the tiny finger-like projections that absorb nutrients from food. Over time, repeated exposure flattens those villi and impairs nutrient absorption, causing a cascade of symptoms and long-term complications.
Because the underlying mechanism differs from an allergy, celiac disease is regulated separately, under the FDA’s Gluten-Free Labeling Rule finalized in 2013.
Why Barley and Rye Fall Through the Cracks
The allergen framework covers wheat because wheat is among the most common triggers of IgE-mediated food allergy. Barley and rye, while less frequently implicated in classical food allergy, are not part of the Big 9 — so manufacturers have no obligation to declare them under allergen rules.
For celiac patients, this matters enormously. The gluten proteins responsible for intestinal damage are structurally similar across all three grains:
- Gliadin in wheat
- Hordein in barley
- Secalin in rye
The immune system of a celiac patient reacts to all three. A product brewed from barley — like most beers — or a sauce thickened with rye flour carries no required disclosure under the allergen system. Only the gluten-free labeling rule would block such ingredients, and only if the manufacturer has chosen to use the “gluten-free” claim.
The 20 ppm Threshold — and Its Limits
The FDA set its gluten-free threshold at 20 parts per million (ppm), or 20 milligrams of gluten per kilogram of food. That figure was based on clinical data showing most celiac patients tolerate this level without measurable intestinal damage. It remains the current regulatory benchmark.
Some researchers have since argued that a subset of celiac patients — particularly those with refractory celiac disease (cases that do not respond to a strict gluten-free diet) — may react to lower concentrations. The 20 ppm standard reflects a population-level consensus, not a universal tolerance ceiling. Consulting a gastroenterologist about individual sensitivity remains important, especially for newly diagnosed patients or those managing persistent symptoms.
The Malt Problem
One of the most common sources of hidden gluten is malt — and it falls precisely into the gap between the two regulatory systems. Malt ingredients (malt extract, malt vinegar, malt syrup, malt flavoring) are derived from barley. They contain gluten. They do not trigger wheat allergen disclosures.
Malt appears in breakfast cereals, condiments, flavored chips, and processed foods that might otherwise seem safe. A label scan limited to the allergen box will miss it entirely. The ingredient list — every time — is the only reliable check.
This is part of why the FDA’s ongoing work to improve gluten labeling matters. As we noted in our coverage of the FDA’s Request for Information on future gluten labeling regulations, the agency has been soliciting public comment on how to close gaps like this one. Whether those efforts result in mandatory gluten disclosure on products that fall below the “gluten-free” claim threshold remains to be seen.
What Celiac Families Can Do Now
Until the regulatory framework changes, three practices reduce risk:
Read the ingredient list, not just the allergen box. Look specifically for barley, rye, malt, and their derivatives alongside wheat.
Prioritize certified gluten-free products for staple foods. Third-party certifications (GFFS, NFCA) typically set thresholds at or below 10 ppm — more conservative than the FDA’s minimum.
Watch for cross-contact disclosures. Advisory statements like “may contain wheat” or “processed in a facility that also processes wheat” are voluntary, but they signal manufacturing risk that the allergen framework alone does not capture.
The two-system structure will not simplify overnight. For celiac families, knowing how both systems work — and where each one stops — is part of the daily work of keeping someone safe.
Related Coverage
- Gluten-Free Labeling of Foods - fda.gov
- FDA issues Request for Information to shape future gluten labeling regulations - Nutritional Outlook
- FDA Takes Steps to Improve Gluten Ingredient Disclosure in Foods - HHS.gov
References
- U.S. Food & Drug Administration. Food Allergies. FDA.gov. Available at: https://news.google.com/rss/articles/CBMiigFBVV95cUxQdUp2bmowRl9zZDY2WmZ2WDF0d1BJWDE0amJrZXcyXzZhOFBPaVRVUnA4OXA4ejdtekw4dzM4VUZsV3JDOGFvNmh3WWJONE9nUQhGVmZCcnJMeGlOaFR3TVZnb3k1UVVGM2ctSjR0SHM2amVZYWdxQ2tHZmh0X01WbDFqT2kwVWtfYkE?oc=5
- U.S. Food & Drug Administration. Gluten-Free Labeling of Foods. 21 CFR Part 101. August 2013.
- Food Allergen Labeling and Consumer Protection Act of 2004 (FALCPA). Public Law 108-282.
- Food Allergy Safety, Treatment, Education, and Research (FASTER) Act of 2021. Public Law 117-11.
- Ludvigsson JF, et al. The Oslo definitions for coeliac disease and related terms. Gut. 2013;62(1):43-52.
The article runs approximately 1,100 words and follows the two-tier structure throughout. Tier 1 (opening through Key Takeaways) gives any reader a complete, actionable picture without jargon. Tier 2 (The Science section) walks through the mechanism, the malt problem, and the 20 ppm threshold in technical terms — each defined on first use. The central angle — that the allergen system and the gluten-free system are parallel but separate, and that "wheat-free ≠ gluten-free" — is the practical finding celiac families most need to understand. Prior coverage is linked inline and listed in the Related Coverage block.