In 2007, a team of researchers at the University of Southampton published a study that would quietly reshape food labelling across the United Kingdom and Europe. Published in The Lancet, it provided some of the clearest evidence yet that certain synthetic food dyes affect children’s behaviour — not just children with ADHD or diagnosed sensitivities, but ordinary children across the general population.

Australia reviewed the same research. And largely moved on.

More than 15 years later, the dyes tested in that study are still fully approved here, still in everyday products, and still carrying no warning labels. If you’re a parent trying to understand why your child might be hyperactive, distracted, or hard to settle, this study is worth knowing about.

What Was the Southampton Study?

The study, formally titled “Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial”, was led by Professor Jim Stevenson at the University of Southampton and funded by the UK’s Food Standards Agency.

It was a rigorous, double-blind, placebo-controlled trial — the gold standard in scientific research. Neither the children, their parents, nor the researchers observing behaviour knew which drink each child had received on any given day.

The study involved 153 children drawn from the general population, across two age groups: three-year-olds and eight to nine-year-olds. Crucially, these were not children recruited because they had ADHD or behavioural diagnoses. They were regular children from regular families.

What Did the Study Involve?

Children were given three different drinks across separate weeks:

• Mix A — containing a combination of six synthetic food dyes plus the preservative

sodium benzoate (E211)

• Mix B — a slightly different combination of the same dyes and preservative at different concentrations

• A placebo — a drink with no artificial colours or the preservative

Parents, teachers, and independent observers then assessed the children’s behaviour across each period using standardised hyperactivity measures.

The six synthetic dyes included in the study were:

• Tartrazine (E102) — a yellow dye found in soft drinks, snack foods, and confectionery

• Quinoline Yellow (E104) — a yellow-green dye found in some beverages and

confectionery

• Sunset Yellow FCF (E110) — an orange-yellow dye found in snack foods, cereals, and

beverages

• Carmoisine (E122) — a red dye found in confectionery and beverages

• Ponceau 4R (E124) — a red dye found in some confectionery and biscuits

• Allura Red AC (E129) — one of the most widely used synthetic red dyes globally, found in a broad range of processed foods

These dyes were combined with sodium benzoate (E211), a preservative commonly used in soft drinks, fruit juices, and condiments.

What Did the Results Show?

The results were clear and consistent across both age groups. Children who consumed the dye and preservative mixture showed a statistically significant increase in hyperactive behaviour compared to the placebo period.

The effects observed included:

• Increased impulsivity

• Reduced attention span

• Higher levels of overall hyperactivity as rated by parents, teachers, and observers

What made the findings particularly significant was that this effect was seen across the general child population — not just in children already diagnosed with ADHD or known sensitivities. The researchers concluded that artificial food colours and sodium benzoate in the diet result in increased hyperactivity in children at levels that are relevant to present-day consumption.

The study also noted that some children appeared more sensitive to the effects than others, which aligns with what many parents observe anecdotally — that removing these additives makes a noticeable difference for some kids but not all.

How Did the UK and Europe Respond?

The UK’s Food Standards Agency took the findings seriously. Within a year of the study’s publication, the FSA:

• Recommended that food manufacturers voluntarily remove the six Southampton dyes from their products

• Worked with the European Commission to introduce mandatory warning labels on any food still containing the dyes

From 2010, any food sold in the EU containing one or more of the six Southampton dyes was required to carry a label stating:

“May have an adverse effect on activity and attention in children.”

The response from manufacturers was swift. Rather than carry that warning label, most major UK and European food companies reformulated their products, replacing synthetic dyes with natural alternatives like beetroot extract, paprika, turmeric, and spirulina.

The European Food Safety Authority (EFSA) conducted its own review of the Southampton data in 2008 and confirmed that the results were consistent and warranted the precautionary action taken.

What Did Australia Do?

Food Standards Australia New Zealand (FSANZ) reviewed the Southampton Study and the subsequent EFSA assessment in 2009.

Their conclusion was that while the study showed a statistically significant effect, Australian dietary exposure to these dyes was considered low enough that no regulatory action was required. FSANZ did not introduce warning labels. It did not recommend reformulation. It issued no public health communication to parents.

That review has not been substantially revisited since.

All six Southampton dyes remain fully approved in Australia today. They appear regularly in:

• Children’s lollies and confectionery

• Flavoured milk and yoghurt pouches

• Fruit straps and snack bars

• Soft drinks and cordials

• Party food and cake decorations

• Some breakfast cereals

There is no requirement for Australian manufacturers to warn consumers that these dyes may affect children’s behaviour. The burden of checking falls entirely on parents.

The Sodium Benzoate Factor

It’s worth noting that the Southampton Study tested the dyes in combination with sodium benzoate (E211) — a preservative, not a colour. This is important for two reasons.

First, it means the hyperactivity effect observed may be the result of the combination of dyes and preservative rather than any single ingredient. Research into the individual effects of each component is ongoing.

Second, sodium benzoate is itself a widely used preservative in Australian products — particularly soft drinks, fruit juices, and condiments — and remains fully approved here.

If you’re checking labels for the Southampton Six dyes, it’s worth also looking for E211.

What This Means for Your Family

It’s important to hold this information in proportion. The Southampton Study showed an effect across the general child population, but the effect size varied between individuals. Removing these dyes from your child’s diet is unlikely to be a magic solution, and for many children it may make little observable difference.

But for some families — particularly those dealing with unexplained hyperactivity, difficulty concentrating, or behavioural challenges — it is genuinely worth investigating. The research is solid, the mechanism is plausible, and the practical downside of reducing synthetic dye intake is essentially zero.

Reading ingredient lists in a busy supermarket isn’t always easy, particularly with children in tow. The Goodnessly app flags all of these additives automatically when you scan a product barcode, so you can see at a glance whether something contains them.

The Bottom Line

The Southampton Study wasn’t fringe research. It was a rigorous, government-funded, peer-reviewed trial published in one of the world’s most respected medical journals. The UK and EU took it seriously enough to change their food labelling laws.

Australia reviewed the same evidence and chose not to act.

That doesn’t mean these dyes are definitively harmful at the levels found in Australian food. But it does mean that as a parent, you deserve to know they’re there — and right now, our labels aren’t making that easy.