Allergens in fish

Fish is a food rich in proteins and essential minerals, which improve many health indicators. That is why it constitutes a very important element in the diet. Its consumption cannot favor the entire population due to the large number of allergic reactions that its ingestion causes.

Characteristics of allergic reactions to fish:

• Allergies to fish may be associated with its own proteins, or with the presence in its organism of anisakis, parasites that can cause allergic reactions.

• People allergic to fish may be sensitive to a single family or to several families of fish.

• Only some people allergic to fish are also allergic to shellfish; cross-reactivity between these foods has not been demonstrated.

• Fish allergies can be severe, and can often develop into anaphylactic shock.

• Asthmatic patients are at increased risk of developing severe reactions.

Characteristics of allergic reactions to fish:

• Allergy caused by fish can last for decades, or for life.It is possible, but not very frequent that breastfed babies present allergic reactions to fish if their mother ingests it.

• In Spain, the fish that cause the most allergic reactions are roosterfish, hake and whiting. Those that cause the least reactions are swordfish, mackerel and tuna.

• Fish allergies can begin at any age.

• In the case of allergies to fish, such as tuna, different preparation methods can alter its allergenicity and promote tolerance. Some individuals tolerate canned tuna, presenting allergic symptoms with fresh tuna.

• In exceptional cases, individuals may have allergic reactions when eating meat from animals such as pigs or chickens that were fed fish meal.

• Proteins in fish during cooking can become airborne and cause allergic reactions.

Allergenic components in fish: The allergens in fish are proteins of the muscular sarcoplasm called parvoalbumins. These proteins are specific for each species.

Most consumed fish families in Spain:

• Condictrios: Dogfish and ray.

• Anguiliformes: Eel, conger eel.

• Cupleformes: Sardines, anchovies, salmon, trout.

• Scombriformes: permit, horse mackerel, albacore tuna, bluefin tuna, mackerel, swordfish.

• Gadiformes: Cod, blue whiting, pout, hake.

• Perciformes: Anglerfish, sea bass, red mullet, grouper, sea bream, bream, sea bream, gilthead bream, dentex.

• Pleuronectiformes: John Dory, turbot, acedia, sole.

• Scorpeniformes : scorpion fish, scorpion fish.

Food products that may contain fish:

• Soups, pizzas, paellas, surimi.

• Wines and alcoholic beverages clarified with fish tails.

• Chickens, pigs or other animals fed with fish meal.

• Gelatins.

• Products enriched with omega-3, from fish oil.

Other products that may contain fish allergens are:

• Medicines in tablets or cod liver suspensions.

• Glues and adhesives used as adhesives for stamps and book bindings.

Treatment and recommendations for fish allergy sufferers:

• The indicated treatment for those allergic to fish is strict diet without fish or fish-containing foods. They should avoid exposure to cooking fumes, because fish protein can be airborne and cause allergic reactions.

• People allergic to fish should avoid consuming other fish species. Generally, they are not allergic to only one species.

• Avoid going to restaurants where fish are offered, they may run the risk of ingesting food contaminated with fish residues in oils, fryers, processing surfaces. They may also suffer a reaction from inhaling particles from cooking vapors.

• Those allergic to fish are recommended to include olive oil, seed oils (sunflower, soybean, corn) and nuts (if tolerated) in their regular diet, in moderate amounts, because of their contribution in unsaturated fatty acids, with characteristics comparable to the healthy fat of fish.