Shellfish in the United Kingdom: label rules and introduction guidance

Is shellfish on the UK's list of 14 allergens?

The FSA lists crustaceans, such as prawns, crabs and lobsters, and molluscs, such as mussels and oysters, as two of its 14 allergens. Each has its own entry and each must be emphasised when present. This is different from the US, where molluscs are not a major food allergen, and the same as the EU. A seafood pasta salad made and packed in a supermarket's own kitchen has had to list both, emphasised, on a full ingredient label since Natasha's Law came into force in October 2021.

The Food Standards Agency (FSA) lists the same 14 allergens as the EU; the EU rules were kept when the UK left and are now assimilated law. On prepacked food, an allergen must be emphasised each time it appears in the ingredient list. Food prepacked for direct sale, packed on the same premises that sell it, needs a full ingredient list with allergens emphasised, the rule known as Natasha's Law since October 2021. Loose food still needs allergen information, given in writing or verbally with a clear written notice.

• Food Standards Agency: Allergen guidance for food businesses

What NHS guidance says about introducing shellfish

The NHS includes shellfish in its list of foods that can trigger allergic reactions, with one preparation warning: do not serve shellfish raw or lightly cooked. Like the other allergens, it is introduced on its own so any reaction can be spotted. The NHS list does not separate crustaceans from molluscs, but because the labels do, it helps to record prawn, crab or mussel by name. If a family member has a seafood allergy, speak to your GP or health visitor before the first taste.

In the UK, the NHS advises introducing the foods that can trigger allergic reactions one at a time from around 6 months, so that you can spot any reaction. If your baby has eczema or there is a family history of allergy, the NHS suggests talking to your GP or health visitor first.

• NHS: Food allergies in babies and young children

Logging shellfish in the app

The UK and EU lists match, so UK families get the same 14-allergen schedule as the EU. In the schedule, shellfish appears as Crustaceans and Molluscs, two separate entries. Each allergen entry moves from not started to introduced, cleared or reaction, and the 14-day window keeps new foods spaced out so a delayed reaction is easier to match to a food. Log prawn, crab or mussel by name, because crustaceans and molluscs are different allergen groups in most countries. If you see a symptom, log it with its severity; the paediatrician report gathers the dates into one PDF for your next appointment. It is a record for you and your doctor, not a diagnosis.