Shellfish is the common food allergen that more often than any other sends food-allergic people, aged 6 years or older, to the emergency department. It’s also one of the top food allergens among adults. In fact, most people with shellfish allergy do not develop it until adulthood. Overall, shellfish allergy affects nearly 7 million people, or about 2.3 percent of the U.S. population.
A shellfish allergy is distinctfrom an allergy to fish. Those who are allergic to shellfish do not necessarily have to avoid fish, and vice-versa.
Within the shellfish family, it is the crustacean group (e.g., shrimp, lobsters, crabs) that causes the greatest number of allergic reactions. Many shellfish-allergic people can tolerate mollusks such as scallops, oysters, clams, and mussels; however, anyone with shellfish allergy symptoms should consult with an allergist before eating any kind of shellfish.
Fortunately, shellfish is an ingredient that is rarely “hidden” in foods where you might not expect to find it. Shellfish may be found in fish stock, seafood flavoring (e.g., crab extract), sushi, and surimi. In the United States, if a packaged food contains shellfish as an ingredient, labeling regulations require the specific shellfish to be listed. These regulations apply only to crustacean shellfish, not to mollusks.
Cross-contact occurs when shellfish comes into contact with another food and their proteins mix during food preparation, cooking, orserving. Therefore, people with an allergy to shellfish should avoid seafood restaurants where cross-contact may occur, even if they intend to order a non-seafood dish. Clear communication with restaurant staff concerning a shellfish allergy is crucial to avoid a reaction caused by cross-contact. Such individuals must also be very careful when ordering fish from a fish market.
Frequently asked shellfish allergy questions
Is inhalation of fumes from cooking shellfish dangerous?
When shellfish is cooked, its proteins may become airborne, and for some sensitive individuals inhalation of the cooking vapors can cause a severe allergic reaction. As a precaution, people who are allergic to shellfish should avoid areas where shellfish is being cooked and should carry an auto-injectable epinephrine (adrenaline) device.
Will I outgrow shellfish allergy?
Shellfish allergy is usually developed later in life, and is usually a lifelong allergy.