The 14 Major Allergens in the UK and What 'May Contain' Means

If you or someone you cook for has a food allergy, the ingredients list becomes the most important part of any pack. UK law makes that easier by naming 14 major allergens that must always be emphasised when they are used as ingredients in pre-packed food.

The Food Standards Agency's consumer guidance lists them as follows.

Allergens can hide behind other names. Milk may appear as whey, casein or butter. Egg may show up in mayonnaise or a glaze. That is one reason the law asks for emphasis, such as bold, italic or a different colour, wherever an allergen appears in the list.

People can also react to foods outside the 14, and a few allergens, such as kiwi, are not on the list at all. If your allergy is to something else, the ingredients list is still your main tool.

A 'contains' statement, or an allergen emphasised in the ingredients, means the allergen is part of the recipe. It is there on purpose.

'May contain' is known as precautionary allergen labelling. It tells you an allergen could be present by accident, through cross-contamination somewhere in the supply chain, such as a shared production line. You may also see wording such as 'not suitable for people with a peanut allergy'.

The FSA's guidance is clear that there is no specific legal requirement to use 'may contain' labels. That means the absence of a 'may contain' warning does not prove a product is free from traces. If you have a serious allergy, it is worth talking to your GP or allergy team about how to treat these warnings, and contacting the manufacturer when you are unsure.

Some food is packed on the same premises where it is sold, before you order it: a wrapped sandwich at a café counter, or a salad pot from a deli. This is called prepacked for direct sale, or PPDS.

Since 1 October 2021, PPDS food must have a label showing the name of the food and a full ingredients list, with allergens emphasised. The change is often called Natasha's Law, after Natasha Ednan-Laperouse, who died after an allergic reaction to a baguette whose packaging did not, at the time, have to list allergens.

The FSA adds that the label should not replace a conversation. If you have an allergy, you can still ask staff, and you should be clear about what you react to.

Restaurants, cafés and takeaways must provide allergen information, either on the menu or by explaining how you can get it. Bakeries, butchers and delis must do the same for any loose item containing one of the 14 allergens.

The FSA suggests checking the menu or calling ahead, being specific when you order, and asking for a manager if you feel your needs are not understood. If you are in any doubt, it advises not eating there.

Apps can help you spot an allergen faster, but they work from product data that can be incomplete or out of date. The pack in your hand is the version that counts.

Do UK food businesses have to use 'may contain' labels?

No. The FSA's consumer guidance says there is no specific legal requirement to label food with 'may contain'. Businesses must still give information that helps people with allergies make choices and manage their condition.

Does 'cereals containing gluten' include oats?

Yes. The legal list names cereals containing gluten, such as wheat, rye, barley and oats. Some people tolerate specially produced gluten-free oats, so follow the advice of your GP or dietitian.

What about loose food, like bread from a bakery counter?

Businesses selling loose food must give you allergen information for any of the 14 allergens it contains. It can be written or spoken, and if it is spoken, staff must tell you where the written information can be found.