E-Numbers and ADHD — The Southampton Six Explained

Six artificial food colours — plus the preservative sodium benzoate — were linked to hyperactivity in children by a landmark 2007 University of Southampton study. In the EU and UK, foods containing any of the six colours must carry the warning: 'may have an adverse effect on activity and attention in children.'

The Southampton study, funded by the UK Food Standards Agency and published in The Lancet, gave drinks containing mixes of these additives to 3-year-old and 8-9-year-old children and found increased hyperactive behaviour compared with placebo. The effect was seen across the general population, not just children with ADHD.

The regulatory response split: the EU introduced the mandatory warning label in 2010 (and many manufacturers reformulated to avoid it), while the US FDA reviewed the same evidence and decided against a warning — which is why American sweets and cereals still commonly contain these dyes.

For parents: the practical takeaway is that these colours are easy to avoid. They appear mostly in brightly coloured sweets, drinks and desserts, they must be named on the label, and natural alternatives (curcumin, beetroot red, anthocyanins) exist for all of them.

The Southampton Six + sodium benzoate

Additive data sourced from Open Food Facts (ODbL licence) and the European Food Safety Authority (EFSA). This page is for general information and does not provide medical or dietary advice.