How to Read a UK Food Label When You Have an Allergy

The definitive plain-English UK guide to reading a food label with an allergy - the bold-allergen rule, the 14 majors, how 'may contain' fits in, and the 30-second routine that catches most mistakes before they hit the trolley.

Short answer. UK law requires the 14 major allergens to be emphasised in the ingredients list every time they appear as a deliberate ingredient - usually in bold. Scan for that emphasis first. Then read the ingredients list in full, watch for hidden names of your allergen, and treat any “may contain” warning as a separate voluntary line, not part of the legal ingredients. This is the anchor - every label-reading rule on the site links back here.

The one thing that makes UK food labels different from most of the world

Under UK law (retained from EU Regulation 1169/2011), the 14 major allergens must be emphasised in the ingredients list every single time they appear as a deliberate ingredient. Usually in bold. Sometimes underlined, sometimes CAPITALISED, sometimes coloured differently. The exact styling can vary between brands, but the requirement to make the 14 stand out visually does not. This is the single most useful thing to know as a UK allergy shopper - the label is designed to catch your eye on your specific allergen before you have finished reading the whole list.

The 14 UK majors are:

1. Celery
2. Cereals containing gluten (wheat, rye, barley, oats, spelt, kamut)
3. Crustaceans (prawns, crabs, lobster) - see fish and shellfish
4. Eggs - see hidden names for egg
5. Fish
6. Lupin
7. Milk
8. Molluscs (mussels, oysters, squid)
9. Mustard
10. Peanuts
11. Sesame
12. Soya
13. Sulphur dioxide and sulphites (above 10 mg/kg)
14. Tree nuts (almonds, hazelnuts, walnuts, cashews, pecans, brazils, pistachios, macadamias)

Each links to the hidden-names page for that allergen. Learning the aliases for your specific allergen is the single most useful thing to build on top of the bold rule.

For the full legal picture: the 14 major allergens UK law must declare.

The 30-second routine

Once you know your allergen and its aliases, the actual shopping decision is fast.

Step 1 - scan for the bold emphasis first. Do not read the whole list. Let your eye skim for anything in bold, capitalised, or otherwise emphasised. If your allergen appears, put the product back. This is the fastest possible check.

Step 2 - read the ingredients list in full. Bold catches the 14 majors. If your allergen is outside the 14 (a specific fruit, a specific spice, a less-common food), you have to read the whole panel. It is listed in descending order of weight, so the first few ingredients make up most of the product.

Step 3 - watch for the hidden names. Milk hides as casein, whey, lactalbumin. Egg hides as albumen, ovalbumin, lysozyme. Soya hides as soya lecithin, edamame. Wheat hides as spelt, bulgur, couscous, seitan. Peanut hides as groundnut, arachis, mandelona. Each hidden-names page linked above gives the working set.

Step 4 - check any allergen box. Some brands repeat the allergen information in a coloured box or “Allergen advice” section beneath the ingredients. It is a helpful reinforcement, but the ingredients list itself is the legal one.

Step 5 - treat “may contain” as separate. More on this below.

Step 6 - decide. Deliberate ingredient means put it back. No deliberate ingredient means read the “may contain” line and apply your rule.

“May contain”, “ingredients”, and “free from” - three different lines

These three phrases appear on UK labels and mean three completely different things.

• The ingredients list = the law. Every deliberate ingredient. The 14 majors emphasised. What you can rely on absolutely.
• “Free from X” = a positive claim by the brand. When brands say “free from” they must have systems in place to verify it, and independent free-from certification exists for gluten and other categories. This is a strong claim.
• “May contain X” = voluntary, unregulated. Precautionary allergen labelling for cross-contamination risk. Applied inconsistently.

Do not confuse them. Free from = safe by design. Ingredients = safe from deliberate presence. May contain = risk call. See may-contain vs the ingredients list and the may-contain decision aid for the detail.

The “may contain” decision block

If your allergen is not in the ingredients list, but a “may contain” line names it, the decision is yours - guided by your allergist. A few factors:

• Anaphylaxis history and severity of past reactions. More severe = stricter rule.
• Poorly controlled asthma - single biggest amplifier of a severe food-allergic reaction. Stricter today if asthma is unsettled.
• How close you are to help. At home near auto-injectors is different from remote hiking or a long-haul flight.
• What you have already eaten or done. Exercise soon after eating, alcohol, and NSAIDs (ibuprofen) all lower the reaction threshold.
• Product category. Bulk chocolate, biscuits, and industrial baked goods share lines with more allergens; a tightly-controlled single-line product is a different risk profile.

Full decision guide: may-contain - should I eat this?.

The categories where labels most often trip families up

Some categories are worth flagging because the label is easier to misread.

• “Vegan” is not “milk-allergy-safe”. Vegan means no animal-derived ingredients. It does not mean no cross-contamination on shared lines. A vegan biscuit made on a line that also makes dairy biscuits can carry a “may contain milk” warning and is not automatically safe for someone with a milk allergy. See free-from vs dairy-free vs vegan.
• “Lactose-free” is not “milk-allergy-safe”. Lactose is the sugar; the protein is what people react to. A lactose-free product often still contains milk protein. See milk allergy vs lactose intolerance.
• “Gluten-free” for wheat allergy. In the UK, “gluten-free” products must contain less than 20 ppm gluten. That is safe for coeliac disease and for wheat-avoiders. Beyond that, wheat allergy is a specific IgE-mediated allergy that is broader than just gluten - some gluten-free products still contain oats or barley traces which could matter for a very cereal-broad allergy.
• “Free from” ranges in supermarkets. These are usually genuinely allergen-managed lines, but read the label every time - the same brand may have different products with different allergen profiles.
• Loose foods and deli counters. Under UK law, allergen information for loose foods (bakery, deli, market stall) must be available, but not always as a printed label - sometimes as a menu card, sometimes verbally. Always ask specifically.
• Pre-packed for direct sale (PPDS) under Natasha’s Law. School lunches, canteen sandwiches, take-away pre-packed items - full ingredients list must be on the pack. See Natasha’s Law explained.
• Imported products. UK-sold products must have a UK-compliant label in English. If the label is only in another language or the 14 allergens are not emphasised, the product is not meeting UK law.

Reading the label at every purchase

The hardest habit and the most important. Recipes change without notice. A product that was safe last month can be reformulated with a new ingredient. “New and improved” quietly means “different”. Reading every label every time is the routine that catches those changes before they cause a reaction.

If you buy the same trolley of products every week, keep a small note (paper or phone) of the ones you have already read this month, and re-check at the start of every new month. That small check is where families most often catch quiet reformulations.

When the label is not the whole story

Two situations where reading the label well is not enough.

• Eating out. Restaurant menus, take-aways, and catered events are person-to-person allergen conversations. Ask direct questions: what is in the dish, how is it prepared, what shared surfaces or oils are used, is there a written allergen matrix. See eating out with a food allergy.
• A product recall. If the FSA has issued an allergen alert on a product you have bought, the label was wrong. Stop, check the batch code, return to the retailer. See an allergen alert was issued - what do I do?.

Where to go next

• You are new to your allergen: the hidden names guides for your specific allergen.
• You are working out a “may contain” call: may-contain - should I eat this?.
• You have kids at school: starting school with a food allergy and allergy-safe school lunches.
• You have grandparents or babysitters helping: allergy rules for grandparents and carers.
• You want to compare scanner apps: allergen scanner apps compared.
• You want to make sure you catch every recall: an allergen alert was issued - what do I do?.

This is the anchor. Every other label-reading rule on the site links back here. Bookmark it, share it with anyone in your household who shops or cooks, and make the 30-second routine the automatic thing.

Written and reviewed by the Food Allergy Lab editorial team.