The relationship between artificial food coloring and attention deficit hyperactivity disorder (ADHD) has been debated for years, but experts haven’t been able to reach a definitive conclusion about the connection. New research on its effects in EEG in college students with ADHD may help build the case against it for all patients with the disorder.

In the European Union, certain additives require a statement on the label that reads “may have an adverse effect on activity and attention in children.” However, the FDA’s official position on artificial food coloring, or AFC, and ADHD is that there is insufficient evidence to establish a connection.

The FDA does not require any particular labeling about the potential relationship between the two, only a listing of the additives. This is a source of frustration for some U.S. medical experts who believe the capacity for harm is there.

A 2017 meta-analysis of double-blind, placebo-controlled studies evaluating dietary interventions in children with ADHD comes down on the side of the FDA. The authors conclude that “further research is required for AFC elimination before advising this intervention as ADHD treatment.”

That leaves parents and physicians thinking “why not?” when it comes to eliminating AFC from a child’s diet. It can’t hurt and it might help. But it sure can make life even more challenging for a busy parent of a child with ADHD.

Recent research in the journal Nutritional Neuroscience may cause the insufficient evidence crowd to look at the relationship anew. This research was performed on college students, not children, but gave us a look at the effects of AFC on EEG patterns.

Students in the study – 18 with ADHD and 11 in the control group – abstained from AFC for two weeks and then were randomized in a double-blind, placebo-controlled crossover challenge, receiving chocolate cookies with or without AFC.

There was a symptom differential at baseline, but attention and EEG showed no difference between the groups. After the AFC challenge, however, there was an increase in posterior mean gamma power, a decrease in posterior relative alpha power, and a “marginal” increase in inattentive symptoms in the ADHD group.

Interestingly, the control group was not affected by AFC in any of the domains studied.

While this study looked at college students, the fact that AFC exerted an objective effect on brain waves raises eyebrows. The authors agree that more research is needed to establish this relationship in college students, so it is certainly needed to examine the relationship in children.

But for those who care for patients with ADHD, it adds weight to the “why not?” approach of removing AFC from ADHD patients’ diets while waiting for a consensus to be reached.