Since the 1970s and the well-publicized advocacy of Benjamin Feingold, there has been public concern that food colorings may cause ADHD-like behavior in children.  These concerns have led the FDA and other food safety authorities to regularly review the scientific literature, and led the UK FSA to commission a study by researchers at Southampton University of the effect of a mixture of the "Southampton 6" and sodium benzoate (a preservative) on children in the general population who consumed them in beverages; the study published in 2007.  The study found "a possible link between the consumption of these artificial colours and a sodium benzoate preservative and increased hyperactivity" in the children; the advisory committee to the FSA that evaluated the study also determined that because of study limitations, the results could not be extrapolated to the general population, and further testing was recommended".
The European regulatory community, with a stronger emphasis on the precautionary principle, required labelling and temporarily reduced the acceptable daily intake (ADI) for the food colorings; the UK FSA called for voluntary withdrawal of the colorings by food manufacturers.  However, in 2009 the EFSA re-evaluated the data at hand and determined that "the available scientific evidence does not substantiate a link between the color additives and behavioral effects"  and in 2014 after further review of the data, the EFSA restored the prior ADI levels.
The US FDA did not make changes following the publication of the Southampton study, but following a citizen petition filed by the Center for Science in the Public Interest in 2008, requesting the FDA to ban several food additives, the FDA commenced a review of the available evidence, and still made no changes.