Undeclared Allergens: Why Food Recalls Keep Missing the Label

The legal framework for allergen labeling in the United States rests on two laws. The Food Allergen Labeling and Consumer Protection Act of 2004, or FALCPA, established the original "Big Eight": milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat, and soybeans. These eight foods account for more than 90 percent of documented food allergies.

The FASTER Act of 2021 added sesame as the ninth major allergen, effective January 1, 2023. Unlike FALCPA, the FASTER Act was self-implementing. No FDA rulemaking was required. The law took effect, and sesame joined the list.

What happened next exposed a structural problem in the regulatory system. Several major commercial bakeries, including suppliers to national restaurant chains, began intentionally adding sesame flour to products that previously contained no sesame. Rather than invest in dedicated production lines or validated cleaning procedures, they chose to add the allergen and declare it on the label.

The FDA's then-Commissioner Robert Califf addressed it publicly: "I don't think anyone envisioned there being a decrease in the availability of products that are safe choices for sesame allergic consumers." An estimated 1.6 million Americans with sesame allergy lost access to previously safe baked goods overnight. The law designed to protect them had instead narrowed their options.

"The FASTER Act was supposed to protect those with sesame allergy," noted FARE, the leading food allergy advocacy organization. "Instead it exposed how far some companies will go to avoid compliance costs."

If you have never worked in a food manufacturing facility, it is easy to imagine allergen control as a straightforward task. Write the recipe, list the ingredients, print the label. Match them up. Done.

The reality is messier. Undeclared allergens typically enter the food supply through one of five failure points.

Cross-Contact on Shared Equipment

Most food manufacturing facilities produce multiple products on the same production lines. Between runs, equipment must be cleaned. But complete allergen removal is not always achieved. Powdered milk and peanut dust can become airborne and settle on adjacent lines. Employees moving between production areas can carry residue on clothing. And rework, the common practice of reincorporating trimmed or excess product from one run into another, can introduce allergens without anyone tracking the change.

Packaging and Labeling Errors

The wrong label applied to the right product is a shockingly common error, especially on shared packaging lines where multiple stock-keeping units run in sequence. Pre-printed label inventories can become commingled in storage. An allergen-containing ingredient may simply never be transferred from the formulation document to the consumer-facing label. In some cases, product is sold in entirely the wrong package.

Supply Chain Opacity

Food manufacturers rely on ingredient suppliers. When a supplier changes sources, reformulates an ingredient, or substitutes a material during a shortage, the new allergen profile does not always make it downstream. Private-label products are especially vulnerable because they pass through multiple tiers of contract manufacturing, each with its own supply chain.

Reformulation Without Label Updates

When a product is reformulated to improve taste, reduce cost, or achieve a clean label positioning, the new ingredient list must pass through an internal label review process. That process sometimes fails. The new formula launches, but the old label stays in circulation.

Regulatory Gaps

The FDA's own guidance makes clear that cross-contact allergens are not legally required to be declared on the label. The "Contains" statement and ingredient list are for intentionally added ingredients only. If milk protein ends up in a dark chocolate bar because the same equipment ran a milk chocolate batch earlier, the label does not have to mention it.

"May contain" and similar advisory statements are voluntary. They are not standardized. They are not enforceable. A consumer with a peanut allergy has no way to distinguish between a "may contain peanut" warning that reflects meaningful risk and one that is added as a blanket legal protection.

Further complicating matters, USDA-regulated products including meat, poultry, and processed egg products follow different labeling rules. Alcohol regulated by the TTB is exempt from FALCPA and FASTER Act requirements entirely. Restaurant and food-service items face no packaged-food allergen labeling obligations at all.

The recall data tells a story of persistent, intractable failure:

2024: 101 allergen recalls, representing 34 percent of all food recalls. The top undeclared allergens were peanuts and tree nuts. Sesame-related recalls declined from 13 to 7, reflecting the FASTER Act's first full year.

2025: 261 allergen recalls, 46 percent of 567 total. Milk recalls rose from 49 to 62. Tree nut recalls rose from 32 to 43. Wheat fell from 58 to 38. Soy remained stable at 47 to 44. Eggs declined from 23 to 18.

Most commonly undeclared in 2025:

1. Milk — 62 recalls
2. Soy — 44 recalls
3. Tree nuts — 43 recalls
4. Wheat/Gluten — 38 recalls

The economic cost of a recall is enormous. The average direct cost is estimated at $10.3 million per event, with 23 percent of recalls exceeding $30 million. These figures cover product retrieval, disposal, customer notifications, regulatory penalties, and lost sales. They do not account for brand damage, lost retail contracts, and shareholder value decline, which typically multiply the direct cost several times over.

None of these numbers capture the cost to consumers. An undeclared allergen in a packaged food is a landmine for someone with a life-threatening allergy. The majority of fatal food-allergic reactions are triggered by food consumed outside the home and by foods the person believed to be safe. A wrong label is not a paperwork error. It is a hazard.

In January 2025, the FDA released two significant guidance documents aimed at food allergens.

The first, an updated Q&A on Food Allergen Labeling, made several notable changes. Coconut and kola nut are no longer classified as tree nuts for labeling purposes. Cross-contact allergens are explicitly not to be declared in the "Contains" statement or ingredient list, a clarification that disappointed many allergy advocates who had hoped for more transparency. Allergen-free claims now require that the allergen is absent even from cross-contact, raising the bar for manufacturers who market products as free from specific allergens.

The second document established a framework for evaluating non-listed food allergens, using four scientific factors: IgE binding evidence, prevalence of allergy in the population, severity of reactions, and allergenic potency of the food. This framework could eventually lead to additional allergens being added to the mandatory labeling list.

Notably absent from both documents was any requirement for standardized advisory labeling. The "may contain" patchwork remains voluntary.

Under the FDA's Preventive Controls for Human Food rule, allergens are treated as chemical hazards. Facilities must conduct a hazard analysis, identify where allergen cross-contact or labeling errors could occur, and implement preventive controls.

The draft guidance establishes three types of allergen preventive controls. Allergen cross-contact controls include validated cleaning procedures, dedicated equipment or production lines, and production scheduling that minimizes risk. Label controls cover label design review, proof approval procedures, and inventory management to prevent label commingling. Supply-chain controls require supplier audits, raw material testing, and verification of supplier allergen programs.

These controls are only as effective as their implementation. The recall data suggests that implementation remains inconsistent. A preventive controls qualified individual, or PCQI, must oversee the food safety plan. But the PCQI's attention is divided across microbial hazards, physical hazards, chemical contaminants, and allergens. When a facility is short on time and resources, allergen control is often the first area to slip.

For the consumer with a food allergy, the most reliable approach is layered. Read the full ingredient list every time you buy a product, even one you have purchased before. Formulations change without notice. Do not rely solely on the "Contains" statement. The ingredient list itself may contain allergens listed by unfamiliar names, and cross-contact allergens are not included in either.

Learn to recognize the alternate names for your allergens. Milk can appear as casein, whey, lactoglobulin, or ghee. Soy can appear as edamame, hydrolyzed vegetable protein, or textured vegetable protein. Wheat can appear as farina, semolina, or modified food starch.

Advisory labels like "may contain" or "manufactured in a facility that also processes" are voluntary and unregulated. Some allergists recommend avoiding all products with such warnings. Others take a case-by-case approach. Discuss the right strategy with your healthcare provider.

For those managing multiple allergies or navigating complex ingredient lists, a scanning tool can identify problematic ingredients in seconds. Using IngrediCheck, you can scan a product barcode and instantly see which of the nine major allergens the product contains, including those listed under obscure names. When every label is a potential risk, a second set of eyes makes the difference.

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