The quick answer: how to check a food label
Before buying or eating a packaged food:
1. Check the exact product
Don't rely on the brand or a previous purchase.
2. Read the complete ingredients list
Look for both familiar and unfamiliar ingredient names.
3. Identify highlighted allergens
UK labels generally emphasise regulated allergens in the ingredients list.
4. Check precautionary statements
Look for 'may contain' and similar warnings.
5. Consider your specific requirements
Milk allergy, lactose intolerance, wheat allergy and coeliac disease require different checks.
6. Check any claims on the packaging
Vegan, plant-based, dairy-free and gluten-free have different meanings.
7. Ask when something is unclear
Contact the manufacturer or food business rather than guessing.
If you cannot establish whether a product is suitable for a diagnosed allergy, follow your allergy-management advice and choose an alternative.
1. Start with the ingredients list, not the front of the packet
Food packaging is designed to attract attention.
The front might say:
- Plant-based
- High protein
- Natural ingredients
- No added sugar
- Vegan
- Gluten-free
- Made with oats
These descriptions can be useful, but they don't necessarily answer your allergy question.
A vegan biscuit, for example, may contain almonds, wheat, soy or sesame.
A gluten-free cake may contain milk, eggs or nuts.
A product advertised as lactose-free may still contain milk proteins.
The full ingredients list is where you should begin.
Example: a plant-based snack
Imagine a packet labelled:
Plant-based protein bar
Ingredients: Dates, peanuts, soy protein isolate, cocoa powder, sunflower oil, natural flavouring.
A plant-based claim does not mean the product is peanut-free or soy-free.
The relevant ingredients still need checking.
2. Look for allergens highlighted in bold
In the UK, 14 allergen categories are regulated under food information rules.
For applicable prepacked foods, allergens used as ingredients generally need to be emphasised within the ingredients list.
Manufacturers often use bold type, although other permitted methods of emphasis may be used.
Example ingredients list
Ingredients: Oats, sugar, milk powder, sunflower oil, hazelnuts, cocoa powder.
Here, milk and hazelnuts are highlighted.
However, bold text isn't the only thing you should read.
The complete list matters because someone may need to avoid ingredients outside the 14 regulated categories.
What are the 14 UK allergens?
They are:
- Celery
- Cereals containing gluten
- Crustaceans
- Eggs
- Fish
- Lupin
- Milk
- Molluscs
- Mustard
- Nuts
- Peanuts
- Sesame
- Soybeans
- Sulphur dioxide and sulphites above the applicable threshold
Read our complete guide to the UK's 14 food allergens.
Does every allergen appear in bold?
No.
The UK list covers specific regulated categories, not every possible food allergy.
For example, someone might be allergic to a food outside those categories.
That ingredient may appear in the ingredients list without the same regulated allergen emphasis.
You must check according to the individual's actual requirements.
3. Learn the unfamiliar names for common allergens
Some ingredients have names that don't immediately reveal their source.
Examples include:
| Ingredient name | What to recognise |
|---|---|
| Casein | Milk protein |
| Whey | Milk-derived ingredient |
| Ovalbumin | Egg protein |
| Albumen | Egg white |
| Arachis oil | Peanut oil |
| Groundnut | Peanut |
| Tahini | Sesame paste |
| Benne | Sesame |
| Spelt | A form of wheat |
| Semolina | Usually made from durum wheat |
| Barley malt | Barley-derived ingredient |
| Gianduja | Traditional chocolate and hazelnut preparation |
| Surimi | Usually processed fish paste |
| Shrimp paste | Crustacean-derived ingredient |
These examples are useful starting points, but some ingredients require more careful interpretation.
For example, lecithin can come from soy, sunflower, egg or other sources.
An unspecified ingredient should not automatically be assigned to one allergen source.
Ingredients with misleading names
Some names sound like allergens but do not necessarily contain them.
Examples:
Lactic acid: Not inherently derived from milk.
Sodium lactate: Not inherently a milk protein ingredient.
Cocoa butter: Derived from cocoa beans, not dairy butter.
Cream of tartar: Not a dairy ingredient.
Vegetable oil: Its plant source may vary.
Lecithin: Can have different sources.
The correct approach is to establish the ingredient's actual source, not make assumptions from part of its name.
For more detailed references, visit Hidden Allergen Names.
4. Understand 'contains' versus 'may contain'
These statements describe different situations.
Contains
A statement such as:
Contains: Milk, Eggs
generally identifies allergens deliberately present in the food under the applicable labelling system.
In the UK, the relevant allergen information for ordinary prepacked food is generally emphasised in the ingredients list.
A separate 'Contains' statement is particularly familiar on US packaging.
May contain
A statement such as:
May contain peanuts.
usually refers to possible unintended allergen presence, often through manufacturing cross-contact.
It does not mean peanuts are deliberately included in the recipe.
Made in a factory that handles nuts
This is another form of precautionary information.
It describes a possible manufacturing exposure, but the wording alone does not quantify the risk for a particular product.
Important distinction
A product without a 'may contain' warning is not automatically free from cross-contact.
Precautionary allergen labelling is generally voluntary in the UK.
For someone with a diagnosed allergy, decisions about precautionary warnings should follow individual clinical advice.
For more detail, read our guide to what 'may contain' means on food labels.
5. Don't confuse allergies with intolerances
Different conditions can require different ingredient checks. Our guide to food allergy vs food intolerance explains the differences in more detail.
Milk allergy versus lactose intolerance
Milk allergy involves an immune reaction to milk proteins.
Lactose intolerance involves difficulty digesting lactose, the sugar in milk.
A lactose-free milk product may still contain casein and whey.
Therefore, lactose-free does not automatically mean suitable for milk allergy.
Wheat allergy versus coeliac disease
Wheat allergy involves an immune response to wheat proteins.
Coeliac disease is an autoimmune condition triggered by gluten.
Someone with coeliac disease needs to avoid gluten from relevant sources, including wheat, barley and rye.
Someone with wheat allergy may have different requirements.
Gluten-free versus wheat-free
A product may meet gluten-free requirements while containing specially processed wheat-derived ingredients.
This is particularly relevant to gluten-free wheat starch.
A gluten-free claim should not automatically be treated as a wheat-free claim.
Read our wheat and gluten ingredient guide.
6. Understand what 'gluten-free' means
In the UK, a food labelled gluten-free must meet the applicable legal standard of no more than 20 parts per million of gluten.
This is a regulated claim.
However, the words gluten-free do not mean:
- Free from milk
- Free from eggs
- Free from nuts
- Free from sesame
- Suitable for every wheat allergy
- Free from every possible allergen
What about oats?
Oats can be contaminated with wheat, barley or rye during growing and processing.
Specially produced gluten-free oats may be suitable for many people with coeliac disease.
However, some people react to avenin, an oat protein.
Follow individual advice.
Read our gluten-free scanner guide.
7. Check the difference between 'vegan', 'dairy-free' and 'milk-free'
These phrases do not all mean the same thing.
| Label claim | What it generally tells you | What it doesn't guarantee |
|---|---|---|
| Vegan | Product is intended to exclude animal-derived ingredients | Absence of allergen cross-contact |
| Plant-based | Describes a plant-focused product | Free from nuts, soy, wheat or sesame |
| Dairy-free | Indicates an absence of dairy ingredients under the claim's context | A universal guarantee against cross-contact |
| Lactose-free | Lactose is absent or reduced to the applicable claimed level | Absence of milk proteins |
| Gluten-free | Meets the applicable gluten threshold | Absence of other allergens |
| Nut-free | A claim about nut ingredients or presence | Suitability for every possible allergy without further checking |
Example: vegan chocolate
A vegan chocolate bar might contain:
Vegan chocolate bar
Ingredients: Cocoa mass, sugar, cocoa butter, almonds, soy lecithin.
It may contain no deliberately added dairy ingredients but still contain almonds and soy.
Always check the relevant allergens.
8. Read labels every time, even for familiar products
Manufacturers can change ingredients.
A product you've bought for years may be reformulated.
Changes might involve:
- A different ingredient supplier
- A replacement oil
- A new flavouring
- A different thickener
- A changed manufacturing site
- An added allergen
- Updated precautionary information
The packaging may look almost identical.
Can the barcode stay the same when ingredients change?
Sometimes, yes.
A barcode identifies a product in a commercial identification system.
It does not necessarily encode the complete current ingredient list.
Depending on the type of product change and applicable identification rules, an updated formulation may continue under the same barcode.
This is why checking the physical label remains important.
Read our guide to barcode scanning versus ingredient label scanning.
9. Check imported and foreign-language foods carefully
Food labels can become harder to interpret when the ingredients are written in another language.
Common examples include:
| Language | Milk | Egg | Peanut |
|---|---|---|---|
| French | Lait | Œuf | Arachide |
| Spanish | Leche | Huevo | Cacahuete / Maní |
| German | Milch | Ei | Erdnuss |
| Italian | Latte | Uovo | Arachide |
| Portuguese | Leite | Ovo | Amendoim |
These are examples of common words, not a complete translation reference.
Regional terminology, ingredient derivatives and labelling requirements vary.
What if a product has a translated sticker?
Imported foods may have a local-language sticker added to the packaging.
Check that it corresponds to the correct product and covers the relevant ingredient information.
If the original and translated information appear inconsistent, seek clarification.
Can translation apps guarantee accurate allergen information?
No.
Translation and text recognition can make mistakes, especially with small print, curved packaging or unfamiliar terminology.
For a serious allergy, do not rely solely on automated translation.
Read our guide to checking ingredient labels abroad.
10. Check food sold in cafés, bakeries and restaurants
Not every food comes with a conventional ingredients list.
In the UK, food businesses have responsibilities to provide allergen information for relevant foods sold without standard prepacked labelling.
However, how the information is supplied depends on the food and how it is sold.
Questions worth asking
- Does this dish contain the allergen?
- Are any sauces, dressings or garnishes made with it?
- Are ingredients or preparation methods changed regularly?
- Is shared equipment used?
- Can the business provide reliable information about cross-contact?
If staff cannot provide reliable information, don't guess.
What is Natasha's Law?
Natasha's Law is the commonly used name for UK changes requiring applicable food prepacked for direct sale to display the food name and a full ingredients list with regulated allergens emphasised.
The rules took effect across the UK on 1 October 2021.
This can apply to foods such as certain sandwiches prepared and packaged on the premises before being selected by customers.
It does not mean every restaurant meal must have an identical printed label.
11. Be careful with products that contain multiple ingredients
A simple food might have only a few ingredients.
A ready meal may have dozens.
For example:
Chicken and vegetable noodle bowl
Ingredients: Noodles (wheat), chicken, vegetables, sauce (water, soy sauce [water, soybeans, wheat, salt], sugar, sesame oil), seasoning.
The allergens may be present inside compound ingredients such as sauces or seasoning mixtures.
What is a compound ingredient?
A compound ingredient is an ingredient made from two or more ingredients.
Examples include:
- Chocolate
- Sauce
- Seasoning mix
- Biscuit pieces
- Curry paste
- Dressing
The label may provide the component ingredients in brackets or another permitted format.
Don't stop reading when you reach the name of a compound ingredient.
12. What if an ingredient's source is unclear?
Some ingredients can be derived from different sources.
Examples include:
- Lecithin
- Modified starch
- Vegetable oil
- Protein hydrolysates
- Certain flavourings
Applicable allergen declaration rules can require an allergenic source to be identified, but exemptions and product circumstances matter.
If you cannot determine whether an ingredient is relevant to your allergy, contact the manufacturer.
An app should not guess the source of an ingredient simply because one source is common.
13. Don't assume 'free from' means zero risk
Free-from products can be useful for people managing dietary requirements.
However, different claims have different legal meanings and supporting controls.
For example, gluten-free has a specific regulatory threshold.
Other free-from claims must be accurate and not misleading, but their assessment may involve different considerations.
A free-from claim should be evaluated in the context of the person's individual requirements.
For a serious allergy, follow clinical guidance and check the current product.
14. How to teach children and carers to check labels
For families, label checking often involves more than one person.
Parents, grandparents, carers, school staff and older children may all need to understand the relevant ingredients.
Start with the specific allergen
Explain which ingredient or ingredients the person needs to avoid.
Teach common alternative names
For milk, this might include whey and casein.
For peanuts, it might include groundnuts and arachis.
Explain precautionary warnings
Make sure carers understand the difference between an ingredient and a possible cross-contact warning.
Encourage checking every time
Even familiar products should be checked when purchased or used.
Make uncertainty a reason to ask
Children and carers should feel comfortable asking for help rather than guessing.
Keep emergency information available
For someone with a diagnosed serious allergy, follow their individual emergency plan and ensure prescribed medication is accessible as advised.
An ingredient scanner is not a substitute for emergency preparedness.
15. A practical example: checking a packet of biscuits
Imagine the following fictional label:
Chocolate oat biscuits (fictional)
Ingredients: Oats, sugar, vegetable oil, milk chocolate (sugar, cocoa butter, milk powder, cocoa mass), soy lecithin, raising agents.
May contain peanuts and tree nuts.
Let's check it.
Step 1: Read the product name
The name doesn't tell us everything.
Step 2: Read the ingredients
Milk powder is listed.
Soy lecithin is also listed.
Step 3: Check highlighted allergens
Milk and soy are declared.
Step 4: Read the precautionary statement
Peanuts and tree nuts are mentioned as possible cross-contact allergens.
Step 5: Consider the person's requirements
For someone with milk allergy, the deliberate milk ingredient is relevant.
For someone with soy allergy, the soy-derived lecithin requires consideration according to their individual guidance.
For someone with peanut allergy, the precautionary warning matters.
Step 6: Make an informed decision
Use the person's allergy-management guidance.
Do not assume that a food is suitable simply because a particular allergen isn't deliberately included.
16. How ClearaScan helps with food label checking
ClearaScan is designed to help people review the ingredients printed on the products they're holding.
Instead of relying solely on a barcode database, it reads photographs of ingredient labels.
Read the actual label
Take a photograph of the ingredients list.
For long or curved labels, additional photographs may be needed.
Check your Ingredient Guard
Recognised ingredient text is checked against the rules you've selected.
Check multiple profiles
Different family members can have different Ingredient Guards.
One captured label can be checked against multiple profiles.
Review the result
A flagged match identifies recognised information relevant to a selected rule.
A result with no flagged matches does not guarantee that the product is safe.
Save products for future reference
Trusted Products helps users keep track of previously checked items and reminds them to recheck.
ClearaScan supports label checking. It cannot replace careful reading, manufacturer clarification or an individual allergy-management plan.
