Fish is one of the 14 major food allergens. Unlike some allergies which predominantly develop in infancy or childhood, a fish allergy may manifest in adulthood. Today we are shining a spotlight on fish allergies and the details you should look out for in allergen ingredient information.
An allergy to a fish species doesn’t rule out all types of seafood. Having an allergy to finned fish, like tuna and salmon, does not necessarily mean you will have an allergy to crustaceans, such as shrimp, crab, and lobster. Some allergists, which specialise in diagnosing and treating allergic conditions, might tell you to stay away from all types of fish; it is recommended to speak to an allergist before trying out other types of fish.
Fish Allergy Triggers
Research from the National Library of Medicine states that there are a number of potential allergen triggers in fish. One of the most common is a protein called parvalbumin. Parvalbumin levels in carp are up to 100-times higher than in mackerel or tuna, which is one explanation why people with fish allergies can tolerate certain species.
Recent studies have highlighted two other proteins, vitellogenin (a fish folk protein) and tropomyosin (a filamentous muscle protein), have also been documented as causing allergic reactions, as well as fish roe.
Both raw fish and cooked fish can cause allergic reactions. The parvalbumin protein can survive heat, which means you can have a fish allergy reaction whether the fish is raw, boiled, roasted, fried, or grilled.
Other fish proteins allergens include:
- Enolases;
- Aldolases;
- Fish gelatin.
While other allergies might subside or have fewer effects as you grow older, studies show that fish allergies can last for a lifetime.

Food people Should Avoid if They Have a Fish Allergy
As mentioned earlier it’s common to be allergic to finned fish, so it’s important to avoid species such as:
- Anchovy
- Bass
- Catfish
- Cod
- Flounder
- Grouper
- Haddock
- Hake
Fish can also appear in unexpected sources, particularly in sauces such as barbeque sauce, worcestershire sauce, and caesar salad dressing. If you’re unsure what’s in your food, it’s important to check the ingredient labels or ask staff if ordering at a restaurant.
Fish Allergy Symptoms
Fish allergy symptoms vary significantly; they could be mild or even have a life-threatening effect. They include:
- Tingling or itching in the mouth
- Rashes and itchiness
- Sneezing
- Swelling
- Difficulty or inability to swallow
- Difficulty breathing and shortness of breath
- Stomach pain and/or diarrhoea
- Nausea and/or vomiting
- Anaphylaxis, which can be fatal (symptoms include: difficulty breathing or speaking, dizziness, or a swelling tongue)
Anaphylaxis is a less common symptom; however, it is more severe, and may require epinephrine and medical care. Anaphylaxis may start with mild symptoms before steadily worsening, and if suffering from an anaphylactic attack then an ambulance should immediately be contacted.
Those that have a fish allergy, or care for someone with a fish allergy, must carefully read all food items labels before consumption.
How Frequently Can Food Allergen Information Change?
As of 2022, in the UK there are 14 major food allergies that must be declared, and allergy information updates will depend largely on the Food Standard Agency (FSA). The FSA set up the Food Allergy and Intolerance Research Programme to research food allergies and provide the public and food businesses with the most recent information on allergens.
If you have a fish allergy, the best way to stay ahead of the curve is to keep up to date with the FSA’s allergy alert. You will get information on allergy errors and product recalls that could endanger consumers, and receive up-to-date allergy information.
What Should Your Allergen Ingredient Information Include?

It’s essential that food businesses display the 14 major allergens on food labels and menus so that consumers can clearly identify the allergens they avoid.
Food products and dishes come in different forms; typically categorised as pre-packed or non-prepacked. The dissemination of allergy ingredient information differs with each form, but the principles surrounding allergy information are the same. Information about contained allergens must be clearly communicated. Consumers should be aware of the allergen information of their food before consumption.
Here are details that should be included in an allergen ingredient information for food manufacturers/food producers:
- Allergen information must be included in bold, highlighted, or in contrasting colours.
- Allergen information should be referenced to the allergy. For fish allergy, a clear reference will look like this, Nam Pla (FISH) or Surimi (FISH)
- Allergen advice information should be clearly displayed. For example, allergen advice could say “ Contains soya, see ingredients in bold”
You should look out for fish allergy information on the containers for prepacked foods. Ensure the ingredients are clearly stated. While non-prepacked food is important, the recipes or dishes are clearly explained.
For non-prepacked food, the allergen information can be provided at two stages. The first stage is before a purchase is made, and this can be done on the website through written menus or orally before an order is placed.
The second stage is at the point of delivery. The FSA requires food businesses to place written menus or provide an oral description of the menu through the phone.
LiberEat Allergen Detection Technology
Food allergen rules and regulations continue to change and evolve. Food businesses must be vigilant when working with ingredients that contain allergens, and exercise due caution when providing ingredient and allergen information to consumers.
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Sources
Fish Allergy | Causes, Symptoms & Treatment | ACAAI Public Website
Food allergy and intolerance | Food Standards Agency
Finned Fish Can Cause Allergic Reactions, Too | Premier Health
Fish Allergens at a Glance: Variable Allergenicity of Parvalbumins, the Major Fish Allergens | PMC
The Food Allergy and Intolerance Research Programme | Food Standards Agency