Let’s Dish About Shellfish

Lately, we’ve been hearing a lot about shellfish allergy. That may be because a recent study lists shellfish as the most common food allergy among American adults. Adult food allergies are also on the rise—indeed, 1 in 10 American adults (~26M) has a food allergy. 

Shellfish Allergy Prevalence & Severity

According to the study, shellfish food allergies affect approximately 7M American adults. Among this population, nearly 60% have experienced a severe reaction, and almost HALF developed their food allergy as an adult. If you look at other common food allergens, the percentage developed in adulthood is significantly smaller: milk 23%, tree nuts 35%, peanuts 18%, and eggs 29%. 

What Are Shellfish?

Put simply, shellfish are aquatic animals with shells. Most live in saltwater, some live in freshwater, and there are many different types. Each contains different proteins, which is why you may be allergic to some, and not others! Crustaceans, for example, include crab, lobster, shrimp, prawn, and crayfish. Mollusks include clams, oysters, scallops, squid, mussels, cuttlefish, octopus, and snails.

Interestingly, insects and shellfish belong to the same animal phylum: Arthropoda. Arthropoda are animals with external skeletons, no backbones (invertebrates), segmented bodies, and jointed legs. Over a million species of animals are categorized as Arthropoda. You may have heard of lobsters being referred to as the cockroach of the sea—that’s why!

Shellfish Allergy Symptoms

Shellfish allergy symptoms often develop within minutes after ingestion. It’s important to seek treatment from emergency personnel if you are experiencing serious symptoms, as they may lead to anaphylaxis. Shellfish allergy symptoms may include: 

• Hives, itching, or eczema 

• Facial swelling

• Wheezing or congestion

• Abdominal pain, nausea, diarrhea, or vomiting

• Dizziness

• Anaphylaxis

Airborne Allergies to Shellfish  

This past year, we wrote a blog covering all the major need-to-know facts about airborne allergens. According to the American Academy of Allergy, Asthma and Immunology, anaphylaxis from airborne allergen exposure is rare. Airborne exposure to shellfish is more likely to trigger milder reactions, such as difficulty breathing, itchy eyes, and/or a cough.

Since there is currently no shellfish allergy cure, best practices include strict avoidance of the food and having emergency medicines at the ready. When the Allergy Amulet launches, keeping this tool in your “food allergy toolbelt” will be a great management best practice as well. 😉 In the meantime, make sure you thoroughly read labels and menus (shellfish can hide in foods such as glucosamine, bouillabaisse, and Worcestershire sauce), and keep your distance in areas where you know shellfish will be prepared or processed. 

Bon appétit!

- Meg and the Allergy Amulet Team