Ingredient · Color
Red 40
The most widely used synthetic red dye in the US food supply, made from petroleum feedstocks. It is purely cosmetic — it adds colour and nothing else — and appears in drinks, sweets, cereals, and some medicines.
also known as Allura Red AC, E129, FD&C Red No. 40
Red 40 carries no nutritional function, which is what separates a colour from an ingredient doing real work in a formulation.
In the EU, foods containing it must display the warning "may have an adverse effect on activity and attention in children", a requirement introduced after the 2007 Southampton study. No equivalent US label warning exists, so the same product can be sold either side of the Atlantic with different disclosure — which is why the dye is flagged here.
Why it’s classified this way
Classified High risk: no nutritional function, and EU law requires a behavioural warning label that has no US equivalent.
References
- Southampton study (McCann et al., 2007)
- EU Regulation 1333/2008 Annex V