What is a Fish Allergy?

A fish allergy is an adverse response or overreaction of the body’s immune system to the proteins in fish or products that contain fish. When fish is eaten, the body sees the proteins from fish as a foreign invader, sending out chemicals to defend against it. Those chemicals are what cause the symptoms of an allergic reaction. 


👥 How common is it?

Many food allergies are usually first observed in babies and young children. However about 40% of sufferers experience their first allergic reaction in adulthood. Finned fish is one of the most common food allergies, particularly salmon, tuna and halibut, and is usually lifelong.


Symptoms of Fish Allergy

An allergic reaction to fish can bring on many symptoms. These include hives or a skin rash; nausea, stomach cramps, vomiting and/or diarrhoea; stuffy or runny nose, headaches, and asthma. 

🚑 Anaphylaxis

Although less common, some allergy sufferers are also at risk of having a potentially life-threatening anaphylaxis reaction. In extreme cases there could be a dramatic fall in blood pressure, the person may become weak and floppy, and may have a sense of something terrible is happening. This may lead to collapse and unconsciousness. On rare occasions, death can occur.

It is important to be able to recognize and manage reactions quickly in order to prevent serious health consequences. The first line of action for anaphylaxis is the timely use of epinephrine which is available by prescription in a self-injectable device.

Symptoms of an allergic reaction to food

If you are concerned that you or your child may have an allergy, you should consult with a medical professional or a Registered Nutritionist or Dietitian.

If your child is diagnosed with a fish allergy, it’s important to inform all people involved in the child’s care. This includes their nursery, school, and after-school clubs, as well as grandparents, relatives, and the parents of their school friends.


Managing a Fish Allergy

The most obvious way of managing an fish allergy is to avoid eating fish. However those who are allergic to one type of fish are not necessarily allergic to all fish. Having an allergy to a finned fish does not mean that you are also allergic to shellfish, although it is advised that you get tested for this as well.

🛒 Store bought food

Fish is one of the major allergens in the UK & USA and must be legally listed on all packaged foods. It’s often found in prepared foods such as Worcestershire sauce and caesar salad, and it’s a popular ingredient in asian cuisine. Even imitation crab and some fortified fruit juices may contain fish, therefore it’s important to thoroughly check all food labels.

🍽 Eating out

It is also advised that fish allergy sufferers should avoid touching fish and steer clear of fish markets and seafood restaurants. This is due to an increased risk of cross contamination. While restaurant staff may take significant steps to avoid cross contamination, fish protein could potentially be present in steam from the cooking process.


🐟 Replacements for fish products

Fish oil supplements are often taken by people for the Omega 3 fatty acids. Your registered dietitian or a medical professional can help you find a similar supplement that suits both your allergen and nutritional needs. Krill & algae, for example, are great alternatives!

Edible seaweed, also known as nori, is often used to give foods a ‘fishy’ flavour. Due to its growing popularity you should be able to find nori sheets anywhere that sells sushi ingredients. It’s a vital ingredient in ‘tofish & chips’, and vegan ‘fish’ sauce.


Please note: This Spoon Guru Fact Sheet should be used as a source of information only. It should not be used as a replacement to nutritional advice from an accredited medical professional.

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