One-page reference
What's actually in the packet
Colorings, oils, sweeteners and preservatives — the numbers you'll see on a label, what each one is doing there, and the cautions worth knowing, with a source behind every claim. One position we'll state plainly: no artificial color earns a clean bill of health here. They add nothing but appearance, so every synthetic dye on this page is rated at least worth limiting. Elsewhere the picture is more mixed — some additives do real work, and a few matter enormously if you have asthma, PKU, a dye sensitivity or a dog in the house.
Looking for one specific ingredient? The searchable additive glossary maps label names and brand aliases to their E numbers, with the citations attached.
- Generally fine
- Worth limiting
- Avoid or ask first
Artificial colors and their numbers
Six dyes — E102, E104, E110, E122, E124 and E129 — are the "Southampton six". Since 2010, EU and UK products containing them must carry the line "may have an adverse effect on activity and attention in children". That label is the reason most British manufacturers quietly switched to beetroot, paprika and turmeric instead. US products still use the FD&C numbers freely, so an imported version of the same sweet often has a very different ingredient list.
| Color | Number | Where you meet it | What to know |
|---|---|---|---|
| Tartrazine (FD&C Yellow 5)Worth limiting | E102 | Soft drinks, sweets, cereals, packet sauces, some medicines | One of the 'Southampton six'. Linked to increased hyperactivity and inattention in some children; rare urticaria in sensitive adults and people with aspirin sensitivity. |
| Quinoline YellowWorth limiting | E104 | Sweets, smoked fish, some cosmetics and medicines | Southampton six. Not permitted in food in the US. Carries the EU hyperactivity warning label. |
| Sunset Yellow (FD&C Yellow 6)Worth limiting | E110 | Orange squash, cheese snacks, jellies, apricot jam | Southampton six. Occasional hives and rhinitis reports; hyperactivity warning label. |
| Carmoisine / AzorubineWorth limiting | E122 | Jams, sweets, yoghurts, marzipan | Southampton six. Not permitted in the US. Removed by most UK manufacturers. |
| Ponceau 4RWorth limiting | E124 | Tinned fruit, sausage, sweets, dessert toppings | Southampton six. Banned in the US. Lowest acceptable daily intake of the azo dyes. |
| Allura Red (FD&C Red 40)Worth limiting | E129 | The most-used red in the US — cereals, drinks, sweets, baked goods | Southampton six. Animal work suggests gut-barrier and colitis effects at high intake; human evidence is mainly behavioural in susceptible children. |
| Erythrosine (FD&C Red 3)Avoid or ask first | E127 | Glacé cherries, some sweets and icings | Thyroid tumours in high-dose rat studies. The FDA revoked its food authorisation in January 2025, with phase-out through 2027; already restricted in the EU. |
| Brilliant Blue (FD&C Blue 1)Worth limiting | E133 | Ice lollies, blue sweets, mouthwash | Better tolerated than the azo dyes and not part of the Southampton six, but it is purely cosmetic, so there is no upside to balance against. Absorption rises where the gut lining is damaged. |
| Indigo Carmine (FD&C Blue 2)Worth limiting | E132 | Sweets, ice cream, pet food, medical dyes | Widely permitted with few documented problems beyond rare hypersensitivity and nausea, but again it is decoration only — worth avoiding where you can. |
| Fast Green (FD&C Green 3)Worth limiting | E143 | Tinned peas, sauces, sweets (US) | Not permitted in the EU. Little human data either way. |
| Carmine / cochinealWorth limiting | E120 | Yoghurt, sausage, drinks, cosmetics | Insect-derived, so not vegetarian or vegan. A recognised cause of true IgE allergy, including anaphylaxis in rare cases. |
| Titanium dioxideAvoid or ask first | E171 | Chewing gum, icing, coatings, tablet shells | Banned as a food additive in the EU since 2022 after genotoxicity could not be ruled out. Still permitted in the US and UK. |
| Caramel color III & IVWorth limiting | E150c / E150d | Colas, soy sauce, gravy, dark bread | Class IV can contain 4-MEI, a compound California lists under Proposition 65. Levels in most drinks are far below the levels used in animal studies. |
| AnnattoWorth limiting | E160b | Cheddar, butter, snack coatings — often used as a 'natural' replacement | Natural does not mean inert: annatto is a recognised trigger for urticaria and is excluded on strict Feingold-style programmes. |
Oils, fats and what heat does to them
Two things decide whether an oil is a good choice: how much of it is polyunsaturated (less stable), and how hot you are taking it. Past its smoke point an oil starts breaking down into aldehydes and acrolein — that acrid smell is the signal to throw it out rather than turn the extractor fan up. Three rules cover most kitchens: match the oil to the heat, never reuse frying oil more than two or three times, and keep delicate oils cold and dark.
| Oil or fat | Smoke point | Best used for | Caution |
|---|---|---|---|
| Extra virgin olive oil | 190-207°C | Dressings, low and medium sautéing, finishing | High in antioxidants and monounsaturated fat, and more heat-stable than its smoke point suggests. Repeated deep frying still degrades it and wastes the polyphenols you paid for. |
| Avocado oil (refined) | ~270°C | Searing, roasting, stir-frying | Genuinely high heat tolerance, but frequently adulterated with cheaper oils. Buy from brands that publish testing. |
| Coconut oil | 175-230°C (unrefined vs refined) | Baking, medium-heat frying, curries | Roughly 90% saturated fat and it raises LDL cholesterol. Fine as a flavour choice; not a heart-health food, whatever the packaging says. |
| Butter and ghee | 150°C butter / 250°C ghee | Butter for low heat; ghee for high-heat frying | Butter's milk solids burn early and turn bitter. Ghee removes them, so it handles heat far better — but both are dairy and high in saturated fat. |
| Rapeseed / canola (refined) | ~205-230°C | Everyday cooking, roasting, baking | Cheap, neutral and low in saturated fat. Cold-pressed versions have a much lower smoke point — keep those for dressings. |
| Sunflower, corn, soybean, grapeseed | ~215-230°C | Frying, commercial cooking | High in polyunsaturated fat, which is the least heat-stable type. Reheating the same oil repeatedly produces aldehydes; discard after a few uses and never top up old oil. |
| Sesame oil (toasted) | ~175°C | Finishing, dressings, drizzling at the end | The toasted flavour is destroyed by heat and sesame is a major allergen. |
| Flaxseed, walnut, hemp oil | 107-160°C | Cold use only — dressings, smoothies, drizzles | These oxidise quickly even at room temperature. Refrigerate, buy small bottles, and never cook with them. |
| Peanut oil | ~230°C | Deep frying, wok cooking | Highly refined versions are usually tolerated by people with peanut allergy, but cold-pressed and gourmet versions are not. If in doubt, avoid. |
| Palm oil and shortening | ~230°C | Industrial baking, frying | High in saturated fat with significant deforestation issues. Older partially hydrogenated shortenings contain trans fat and should be avoided outright. |
The heat rules, short version
- Deep frying or searing: refined avocado, ghee, refined rapeseed, peanut.
- Everyday pan cooking and roasting: olive oil, refined rapeseed, ghee.
- Cold only: flaxseed, walnut, hemp, toasted sesame, unrefined nut oils.
- Never: oil that has smoked, oil reused more than a few times, or fresh oil topped into old oil.
- Avoid anything listing "partially hydrogenated" fat — that is trans fat, and there is no safe intake.
Sweeteners and sugar substitutes
The honest summary: for most people, swapping sugary drinks for sweetened ones is a net improvement, and the acceptable daily intakes are far above normal use. The real-world problems are digestive (the polyols), specific and serious (aspartame in PKU, xylitol near dogs), or emerging and unsettled (erythritol and clotting). The WHO's 2023 guidance also advised against relying on non-sugar sweeteners for long-term weight control.
| Sweetener | Number | Where you meet it | What to know |
|---|---|---|---|
| AspartameWorth limiting | E951 | Diet drinks, sugar-free yoghurt, tabletop sweetener, chewing gum | Classified by IARC in 2023 as 'possibly carcinogenic', while the acceptable daily intake was left unchanged — roughly 14 cans of diet cola a day for an adult. Must be avoided completely in phenylketonuria (PKU). Breaks down in heat, so it is poor for baking. |
| SucraloseWorth limiting | E955 | Baking blends, drinks, protein powders, sauces | Heat-stable in principle, but cooking sucralose above ~120°C — especially with glycerol — can generate chloropropanols. Some evidence of effects on gut bacteria and glucose response. |
| Acesulfame KWorth limiting | E950 | Almost always blended with aspartame or sucralose in drinks | Bitter alone, which is why it is nearly always blended. Long-term human data is thinner than for the older sweeteners. |
| SaccharinGenerally fine | E954 | Tabletop sweetener, some medicines | The 1970s bladder-cancer scare was a rat-specific mechanism and was formally delisted in 2000. Metallic aftertaste is the practical drawback. |
| Steviol glycosides (stevia)Generally fine | E960 | Drinks, yoghurt, tabletop sweetener | Plant-derived and heat-stable to about 200°C. Liquorice-like aftertaste. Most retail products are mostly bulking agent — check whether it is blended with maltodextrin or erythritol. |
| Monk fruit (luo han guo)Generally fine | E960d-adjacent | Premium sweetener blends, keto products | Very well tolerated, but almost always sold blended with erythritol — so the erythritol cautions apply to the packet, not the fruit. |
| ErythritolWorth limiting | E968 | Keto baking, sugar-free sweets, monk fruit blends | Zero net carbs and tooth-friendly, but 2023 and 2024 studies linked high blood levels to increased platelet clotting and cardiovascular events. The evidence is observational and contested — worth knowing if you already have heart disease. |
| XylitolWorth limiting | E967 | Sugar-free gum, mints, toothpaste, some baking | Fatal to dogs in tiny amounts — keep it out of reach entirely. A 2024 study also linked higher blood levels to cardiovascular events. Causes wind and diarrhoea above about 30-50 g a day. |
| Sorbitol, maltitol, mannitol, isomaltAvoid or ask first | E420, E965, E421, E953 | Sugar-free chocolate, sweets, 'diabetic' products | The worst offenders for bloating, cramping and diarrhoea, and they are high-FODMAP polyols. Maltitol also raises blood glucose more than the label implies. |
| AlluloseGenerally fine | Rare sugar | Keto syrups, ice cream, baking | Behaves like sugar in cooking and browns well, with minimal glucose impact. Not approved for sale in the EU or UK. Above ~30 g it causes digestive upset. |
| Sugar alcohols vs 'natural' syrupsWorth limiting | Honey, agave, coconut sugar, date syrup | Marketed as healthier alternatives | These are sugar. Agave is around 85% fructose, which is worse for liver fat than table sugar. Treat them as sugar in every diet on this site. |
Preservatives and antioxidants
Preservatives stop food poisoning and rancidity, which is not a small thing — botulism in cured meat is a real risk that nitrites solved. The ones worth avoiding are the synthetic phenolic antioxidants (BHA, BHT, TBHQ), largely because rosemary extract and vitamin E do the same job without the question marks. Sulphites are in a category of their own: for some people with asthma they are genuinely dangerous.
| Preservative | Number | Where you meet it | What to know |
|---|---|---|---|
| BHA (butylated hydroxyanisole)Avoid or ask first | E320 | Cereals, chewing gum, dried meats, oils, snack foods | Listed as 'reasonably anticipated to be a human carcinogen' by the US National Toxicology Program on rodent forestomach tumours — an organ humans do not have. Banned in Japan for many uses; excluded on Feingold-style programmes. |
| BHT (butylated hydroxytoluene)Avoid or ask first | E321 | Cereal packaging, shortening, snack foods, chewing gum | Same family as BHA and often used alongside it. Mixed rodent findings, liver enzyme effects at high doses, and it is one of the first additives removed on elimination programmes. Rosemary extract and tocopherols (vitamin E) do the same job. |
| TBHQ (tert-butylhydroquinone)Avoid or ask first | E319 | Fried fast food, instant noodles, crackers, frying oils | Immune effects in animal work and a low acceptable daily intake. Its presence usually flags a heavily processed, repeatedly fried product. |
| Sodium benzoate / benzoic acidWorth limiting | E210-E213 | Fizzy drinks, squash, pickles, sauces, salad dressings | Combined with ascorbic acid (vitamin C) in a bottle, it can form small amounts of benzene, especially in warmth or light. Part of the Southampton hyperactivity studies. Store drinks cool and away from sunlight. |
| SulphitesAvoid or ask first | E220-E228 | Wine, dried fruit, prawns, packet potato, some fruit juice | Trigger asthma attacks in roughly 5-10% of people with asthma, sometimes severely. Must be declared on labels above 10 mg/kg. Also destroy thiamine (vitamin B1). |
| Nitrites and nitratesAvoid or ask first | E249-E252 | Bacon, ham, salami, hot dogs, some cheese | Form nitrosamines when cured meat is cooked at high heat. Processed meat is a Group 1 carcinogen on this basis. 'Celery powder' cured products are chemically the same thing. |
| PropionatesWorth limiting | E280-E283 | Bread, baked goods, processed cheese | Long-standing mould inhibitor with a good safety record. Reported as a behaviour and migraine trigger by a minority; some elimination programmes remove it. |
| Potassium sorbateGenerally fine | E202 | Cheese, yoghurt, dried fruit, wine, baked goods | One of the better-tolerated preservatives. Occasional skin irritation on contact; no meaningful systemic concerns at food levels. |
| Propyl gallateWorth limiting | E310 | Fats, oils, meat products, chewing gum | Often paired with BHA and BHT. Limited endocrine signals in animal studies; removed from many reformulated products. |
| EDTA (calcium disodium)Generally fine | E385 | Mayonnaise, tinned beans, dressings, fizzy drinks | Binds trace metals to stop rancidity, and can bind dietary minerals such as zinc and iron in the process. A concern only with heavy daily intake. |
| Natamycin, nisin, lysozymeGenerally fine | E235, E234, E1105 | Cheese rind, sliced cheese, wine | Fermentation-derived and generally well tolerated. Lysozyme is egg-derived, so it matters for egg allergy. |
| Parabens (in food)Worth limiting | E214-E219 | Some coatings, fillings and drinks; far more common in cosmetics | Weak oestrogenic activity in laboratory studies. Propyl versions were removed from EU food use in 2004; where you meet them now is usually skincare. |
Where this comes from
Every caution above links to its primary source in the table itself. Those links point at four kinds of evidence, and it is worth knowing which is which: regulator opinions (EFSA, FDA, FSA) set the legal position and the acceptable daily intakes; agency hazard reviews (IARC, the US National Toxicology Program) grade the strength of evidence, not the size of the risk; individual studies are the newest and least settled layer; and public-health bodies (WHO, AHA) translate the rest into advice. This page was last reviewed in August 2026, and regulations change — where a link and this summary disagree, the source wins.
- EFSA — European Food Safety Authority
Systematic re-evaluations of every EU-permitted additive, with acceptable daily intakes.
- US FDA — food and color additives
US authorisations, the color additive status list and labelling rules.
- UK Food Standards Agency
UK additive rules, allergen labelling and the colors-and-hyperactivity warning.
- IARC / WHO
Hazard classifications for aspartame, processed meat and related compounds.
- US National Toxicology Program
Report on Carcinogens — the source for the BHA listing.
- PubMed / peer-reviewed literature
The Southampton trial, the erythritol and xylitol papers, and the frying-oil chemistry work.
Reading a label in ten seconds
- Ingredients run in descending order by weight. If sugar, syrup or oil appears in the first three, the rest of the label matters less.
- A color with a number and no plant name behind it is synthetic. 'Beetroot red' and 'paprika extract' are colors too, just not azo dyes.
- 'No artificial colors' on the front does not cover flavourings, preservatives or sweeteners. Turn the packet over.
- Allergens are always in bold in the UK and EU. Sulphites above 10 mg/kg must be declared.
- 'Sugar-free' usually means polyols. If you bloat after sugar-free sweets, that is the maltitol, not you.
- 'Natural' has no consistent legal meaning for additives. Carmine, annatto and caramel color are all natural.