The 9 major food allergens in the US (FALCPA and sesame)

Updated 29 October 2026 · By IngrediLens

In the United States, food labels must declare nine major food allergens. The rules come from the Food Allergen Labeling and Consumer Protection Act of 2004 (FALCPA) and the Food Allergy Safety, Treatment, Education, and Research Act of 2021 (FASTER Act), which added sesame. The FDA enforces them for most packaged food. Meat, poultry and most egg products fall under the USDA.

The nine

Together these account for most serious food-allergic reactions in the US, according to the FDA. Other foods can still cause allergies.

How allergens appear on a US label

Each major allergen in a product must be named at least once, in one of two ways:

• In the ingredient list, either as the common name ("milk", "wheat flour") or in parentheses after a technical name: "casein (milk)", "lecithin (soy)", "semolina (wheat)".
• In a "Contains" statement directly after or next to the ingredient list, such as "Contains: Milk, Egg, Wheat." If a company uses a "Contains" statement, it must list all major allergens in the food.

The allergen must be declared even when it is in a flavoring, coloring or incidental additive. Unlike in the EU, there is no requirement for bold text. Some brands use bold anyway.

Tree nuts: which ones count

Under the January 2025 FDA guidance, the tree nuts that must be declared are a shorter list of commonly allergenic nuts, including almond, Brazil nut, cashew, hazelnut (filbert), macadamia, pecan, pine nut, pistachio and walnut. Coconut and several rarely eaten nuts were removed. If you are allergic to a nut that is not on the list, look for it as an ordinary ingredient name. Hidden names for nuts are in hidden peanut and tree nut names.

What US labels do not cover

• Other allergens. Mustard, celery, lupin and molluscs (clams, mussels, squid) are not major allergens in the US, although they are in the EU. See the 14 EU allergens.
• Barley, rye and oats. Only wheat is a major allergen. People with coeliac disease need to read for barley, rye and malt separately, or choose products labeled "gluten-free". See hidden gluten.
• Highly refined oils. Oils made from an allergen (such as highly refined soybean or peanut oil) are exempt from allergen labeling.
• Cross-contact. "May contain" is voluntary. See what "may contain" means.
• Restaurant food. FALCPA covers packaged food. Restaurants are not required to label allergens, so ask staff directly.

Sesame since 2023

Sesame labeling became mandatory on 1 January 2023. Foods already on the market before that date did not have to be relabeled, so older stock could lack a sesame declaration for a while. The FDA has also noted that some manufacturers responded by adding sesame to products and labeling it, rather than separating production lines. A bread you once ate safely may now contain sesame, so re-read labels. More in sesame, mustard, celery and lupin.

How IngrediLens helps

IngrediLens can use the nine US major allergens as filters, along with EU allergens or your own keywords. It reads the ingredient list and the "Contains" line with your iPhone camera and highlights matches, including technical names like casein, albumin or tahini, and "may contain" statements. Everything stays on your iPhone. The app can miss text on damaged or glossy labels, so always confirm on the pack.