Searching 10 databases for double-blind placebo-controlled trials on the effects of artificial food dyes, Schab and Trinh found 15 that met their criteria.
QUOTE: “Our meta-analysis supports the hypothesis that AFCs (artificial food colorings) promote hyperactivity in hyperactive children, as measured on behavioral rating scales.
QUOTE: ”Despite indications of publication bias and other limitations, this study is consistent with accumulating evidence that neurobehavioral toxicity may characterize a variety of widely distributed chemicals. ”
NOTE: Explaining why his results are not consistent with the Kavale & Forness (1983) meta analysis, Schab says that this analysis included two trials they had overlooked and two that were published later; three of these were large, which increased the power of this meta-analysis.