The Big 9 Food Allergens
Nearly all serious allergic reactions in the United States are caused by a short, defined list of foods. Knowing that list cold — and understanding that an allergy is an immune response, not a preference or an intolerance — is the foundation of allergen-safe service. This chapter fixes the nine major allergens and the difference between a reaction, an intolerance, and anaphylaxis.
The nine major allergens
U.S. law recognizes nine major food allergens that account for the overwhelming majority of allergic reactions: milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat, soybeans, and sesame. The first eight were established by the Food Allergen Labeling and Consumer Protection Act (FALCPA); sesame was added as the ninth by the FASTER Act of 2021, effective January 1, 2023. Note the careful distinctions the list makes: fish and crustacean shellfish are separate categories, and peanuts (a legume) are separate from tree nuts. A guest allergic to one is not necessarily allergic to the other, so staff must never collapse these groups together.
Allergy vs. intolerance
A food allergy is an immune-system response in which the body treats a normally harmless food protein as a threat. Reactions can range from hives and stomach upset to life-threatening anaphylaxis, and they can be triggered by trace amounts. A food intolerance (such as lactose intolerance) is uncomfortable but is a digestive issue, not an immune response, and is not life-threatening. Because the two are easy to confuse, staff should treat every stated allergy as serious rather than assuming a guest 'just doesn't like' a food.
Recognizing anaphylaxis
Anaphylaxis is the most dangerous outcome: a rapid, whole-body reaction that may include swelling of the lips, tongue, or throat, difficulty breathing, wheezing, a drop in blood pressure, dizziness, or loss of consciousness. It can develop within minutes of exposure and is treated with epinephrine and immediate emergency care. Every team member should be able to recognize these signs, because fast action — calling 911 and assisting with an epinephrine auto-injector per policy — can save a life.