E-numbers are codes for food additives that have been safety-assessed and approved for use in the UK, such as colours, preservatives, thickeners and sweeteners. Most people eat them without any problem, but a minority notice symptoms after particular additives, most often certain preservatives, colours, sweeteners or thickening gums.
Additive sensitivity usually means reacting to one or two specific additives, not to E-numbers as a whole. Many E-numbers are natural substances, including vitamin C and the red colour from beetroot, so the code alone tells you little about whether something will suit you.
What do E-numbers actually mean?
An E-number shows that an additive has been assessed and approved. According to the Food Standards Agency, an additive is only approved if it has been shown to be safe for its intended use, there is a genuine technical need for it, and it does not mislead the consumer (FSA guidance on food additives).
On a label, each additive must be listed by what it does, followed by its name or E-number, for example “preservative: sodium benzoate” or “colour: E 100”.
| Range | Main job | Examples |
|---|---|---|
| E100s | Colours | E 100 Curcumin, E 102 Tartrazine, E 162 Beetroot red (betanin) |
| E200s | Preservatives and acids | E 200 Sorbic acid, E 211 Sodium benzoate, benzoic acid, E 270 Lactic acid |
| E300s | Antioxidants and acidity regulators | E 301 Sodium L-ascorbate (Ascorbic acid), E 338 Orthophosphoric acid, Phosphoric acid |
| E400s | Thickeners, gelling agents and stabilisers | E 412 Guar gum, E 415 Xanthan gum, E 440 Pectin, amidated pectin |
| E900s | Glazing agents and sweeteners | E 903 Carnauba wax, E 904 Shellac, E 951 Aspartame |
Which additives do people most often react to?
Preservatives
Benzoates such as E 210 Benzoic acid and E 211 Sodium benzoate, benzoic acid are found in soft drinks, sauces and pickles. Sorbates such as E 200 Sorbic acid and E 202 Potassium sorbate, sorbic acid turn up in cheese, baked goods and dried fruit. People who react to these often describe flushing, itching or a rash. Benzoic acid also occurs naturally in some fruits and spices, and people sensitive to it sometimes react to salicylates too; our guide to salicylate sensitivity explains the overlap.
Sulphites
Sulphites (E220 to E228) preserve wine, dried fruit, some sausages and soft drinks. They are one of the 14 allergens that must be declared on UK labels above a set level, and they are more likely to trouble people with asthma. Our guide to alcohol intolerance covers sulphites in wine.
Colours
Six colours, including E 102 Tartrazine and E 122 Carmoisine, must carry the warning “May have an adverse effect on activity and attention in children” on UK packaging. Some people also report itching or rashes after certain colours. Natural colours are not exempt: cochineal (E 120), made from insects, can occasionally cause allergic-type reactions.
Thickeners and gums
Gums such as E 412 Guar gum, E 415 Xanthan gum and E 414 Gum arabic are types of fibre that gut bacteria ferment. In larger amounts they can add to wind and bloating. They are common in gluten-free baking, sauces, dairy-free drinks and reduced-fat foods.
Sweeteners
Sugar alcohols such as E 953 Isomalt and E 967 Xylitol can have a laxative effect in larger amounts, while intense sweeteners such as E 951 Aspartame are used in tiny quantities. Our guide to sweetener sensitivity covers these in detail.
Wheezing, swelling of the lips or throat, hives or difficulty breathing after food or drink need urgent medical help (call 999 if breathing is affected). Intolerance testing is not a substitute for allergy testing.
How do you read a label for additives?
- Look for the job word. Colour, preservative, antioxidant, emulsifier, thickener, stabiliser or sweetener comes first, then the name or number.
- Learn both versions. The same additive can appear as a name on one product and a number on another, such as curcumin or E 100.
- Read “free from” claims carefully. “No artificial colours” can still mean natural colours such as beetroot red or curcumin.
- Ask about loose foods. Bakery, deli and takeaway foods may not have a full label, so ask staff.
- Remember non-food sources. Medicines, supplements and chewing gum also contain colours, coatings and sweeteners.
How can you find out which additive affects you?
- Keep a detailed diary. Write down brands as well as foods, and photograph the ingredients list of anything that seemed to cause symptoms. Our food and symptom diary template has space for this.
- Compare labels. Line up the ingredients of the products that caused trouble and look for an additive they share.
- Cook from scratch for two weeks. Simple, unprocessed meals cut most additives out at once.
- Reintroduce one product at a time. Leave two to three days between each, starting with the ones you miss most.
Are natural additives easier to tolerate?
Not necessarily. Many additives are substances that exist in nature, such as vitamin C (E 301 Sodium L-ascorbate (Ascorbic acid)), E 162 Beetroot red (betanin), E 140 Chlorophylls and chlorophyllins and E 440 Pectin, amidated pectin from fruit. A natural origin does not guarantee you will tolerate an additive, and a synthetic one is not automatically a problem. Your own diary is a better guide than the label’s marketing.
Where hair sample testing fits
Additive reactions are hard to pin down because a single product can contain several. Testing can give you a starting point and help you decide which additives to look out for first.
The Ultimate Intolerance Test tests 1,100 items, including E-numbers across colours, preservatives, thickeners, glazing agents and sweeteners, for example E 102 Tartrazine, E 211 Sodium benzoate, benzoic acid, E 415 Xanthan gum and E 951 Aspartame. It also covers food, non-food items, pollens, metals, and vitamins and minerals. Sulphites (E220 to E228) and monosodium glutamate (E621) are not separate items on our list.
If you want skincare, household and stress-related items too, the Ultimate Plus Intolerance Test adds them. Our guide to choosing between Core, Ultimate and Ultimate Plus compares the options.
Your report groups items into high, medium and low response, with a 6–8 week elimination plan and a printable food diary. It arrives by email within 3–5 working days of your sample arriving, or 48 working hours with priority.
Frequently asked questions
Are E-numbers bad for you?
No, not as a group. An E-number means the additive has been assessed and approved for use in food, and many are natural substances such as vitamin C or pectin. A small number of people react to specific additives, which is a different question from general safety.
Can you be intolerant to food colourings?
Some people report symptoms such as itching or rashes after certain colours. Six colours, including tartrazine and carmoisine, must carry a warning label in the UK. Comparing the labels of products that caused symptoms can show whether a colour is the common factor.
Why does xanthan gum make me bloated?
Xanthan gum and similar gums are fibres that bacteria in your gut ferment, which produces gas. Small amounts rarely cause problems, but they can add up if you eat a lot of gluten-free or reduced-fat products that rely on them.
Do additives in medicines count too?
Yes. Tablets, liquid medicines and supplements can contain colours, coatings and sweeteners. If you think you react to an additive, ask your pharmacist whether an alternative product without it is available.
This guide is general wellness information, not medical advice. Our test uses bioresonance, a complementary (CAM) method; it does not diagnose allergies, coeliac disease or any medical condition. Speak to a GP if you have severe or ongoing symptoms.
