Can Food Additives Cause or Worsen ADHD?
Artificial food dyes and certain preservatives have been linked to increased hyperactivity and attention difficulties in children — not just in children already diagnosed with ADHD, but in the general population.
The strongest evidence comes from a landmark 2007 randomised, double-blind, placebo-controlled trial conducted at the University of Southampton and published in The Lancet. The study tested two mixtures of artificial colours plus a preservative on 153 three-year-olds and 144 eight/nine-year-olds.
The result: both mixtures caused a statistically significant increase in hyperactive behaviour compared to placebo.
The "Southampton Six" + Sodium Benzoate
These are the seven additives tested in the Southampton study — commonly called the "Southampton Six" (the six dyes) plus sodium benzoate:
| E-Number | Name | Type | Colour |
|---|---|---|---|
| E102 | Tartrazine | Azo dye | Yellow |
| E104 | Quinoline Yellow | Synthetic dye | Yellow |
| E110 | Sunset Yellow FCF | Azo dye | Orange-yellow |
| E122 | Carmoisine (Azorubine) | Azo dye | Red |
| E124 | Ponceau 4R | Azo dye | Red |
| E129 | Allura Red AC | Azo dye | Red |
| E211 | Sodium Benzoate | Preservative | — |
The study found that the combination of these dyes with sodium benzoate (E211) may amplify hyperactivity symptoms in some children. It was not possible to isolate which individual additive was responsible — the effect came from the mixtures.
What the EU Did About It
Following the Southampton study, the European Parliament added a mandatory warning label under EU Regulation 1333/2008. Since July 2010, any food product in the EU containing E102, E104, E110, E122, E124, or E129 must carry the warning:
"May have an adverse effect on activity and attention in children"
This didn't ban the dyes, but it had a major practical effect: many manufacturers reformulated their products to avoid carrying the warning. As a result, these dyes are far less common in EU products today than a decade ago.
Where These Additives Are Still Found
Despite the warning requirement, you can still find these dyes in:
- Cheap sweets and candy — brightly coloured gummies, lollipops
- Soft drinks and energy drinks — especially imported brands
- Flavoured snacks — some crisps and coated nuts
- Ice cream and desserts — especially budget brands
- Sauces and condiments — some curry sauces, mustards
- Imported foods — products from outside the EU often contain these dyes without warnings
Other Additives With Weaker Links to ADHD
Beyond the Southampton Six, some research suggests these additives may also affect attention and behaviour, though the evidence is less robust:
| E-Number | Name | Notes |
|---|---|---|
| E621 | Monosodium Glutamate (MSG) | Some studies associate with behavioural changes; evidence is mixed |
| E951 | Aspartame | Associated with neurological effects in some studies; more research needed |
Genetic Sensitivity
A follow-up to the Southampton study found that genetic differences may make some children more sensitive to food dyes. Children with certain variants in histamine-related genes showed stronger hyperactivity responses to the additive mixtures. This may explain why some children are visibly affected while others are not.
What Parents Can Do
- Read ingredient lists — look for E102, E104, E110, E122, E124, E129, and E211
- Look for the EU warning — "may have an adverse effect on activity and attention in children"
- Choose products with natural colours — look for beetroot extract, paprika, turmeric instead of synthetic dyes
- Scan products with FoodScan.ai — instantly see all E-numbers and their details
- Check our E-numbers database — look up any additive to see what it is and where it's allowed
The Bottom Line
The evidence is clear that artificial food dyes, especially in combination with sodium benzoate, can increase hyperactive behaviour in some children. The EU took this seriously enough to mandate warning labels. While these additives don't cause ADHD, they can worsen symptoms — particularly in genetically sensitive individuals.
If your child has ADHD or shows hyperactive behaviour, eliminating the Southampton Six from their diet is a low-risk, potentially high-reward step worth trying.
Sources
- McCann et al. (2007) "Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children" — The Lancet, 370(9598)
- EFSA Panel on Food Additives (2008) — Assessment of the Southampton study
- EU Regulation 1333/2008 on food additives — mandatory warning labels
