Youngsters with ADHD may have a "unique intolerance" to artificial food colorings, according to a government report released this week suggesting there may be some truth in the common wisdom that synthetic food dyes make children more hyper.
The man-made dyes haven't been proven to cause hyperactivity in most children, nor has research found the dyes to contain "any inherent neurotoxic properties," according to a U.S. Food and Drug Administration staff memo filed after the Center for Science in the Public Interest petitioned the agency to revoke approvals for eight certified colorings. CSPI, a Washington, D.C.,-based consumer gadfly, filed that request on June 3, 2008, and asked the FDA to issue a consumer warning in the interim.
The eight dyes, which give appealingly bright color to beverages, cakes and pies, cereals, candies and snack foods, are FD&C Blue 1 and 2; FD&C Green 3, Orange B, FD&C Red 3, FD&C Red 40, FD&C Yellow 5 and 6.
The FDA distributed the research summary in advance of a two-day hearing in which its Food Advisory Committee, meeting in Silver Spring, Md., will consider any links between food coloring and hyperactivity in children. The committee will advise the FDA if there is a need to take action to protect consumer safety. FDA said that an "expert neurotoxicologist" with the Oak Ridge National Laboratories reviewed two key studies cited in CSPI's petition to get the dyes out of the U.S. food supply, as well as 33 other scientific studies the agency deemed relevant, according to a Sept. 10, 2010, memo made public Thursday. Those included a 2007 study in The Lancet, in which University of Southampton researchers assessed effects of a mixture of artificial colorings and preservatives on the behavior of local British youngsters ages 3 to 4, and ages 8 to 9; and a 2004 meta-analysis in the Journal of Developmental & Behavioral Pediatrics analyzing previous studies addressing the relationship between artificial food colors and behavioral changes in children diagnosed with ADHD.
In its petition, CSPI referred to a diet developed in the 1970s by Dr. Ben Feingold, a California pediatric allergist with prominent positions at Kaiser Permanente Medical Center, to eliminate synthetic dyes, food preservatives and chemicals called salicylates, including aspirin, which "appeared to reduce symptoms of hyperactivity in many children." In the petition, Michael Jacobson, CSPI executive director, called it "medically and ethically unwise to burden hyperactive children and their parents with concerns about foods with synthetic dyes."
On July 20, 2010, a European Union regulation, adopted in July 2008, went into effect requiring that food labels for products containing any of six food colors state that they "may have an adverse effect on activity and attention in children."
Dr. L. Eugene Arnold, a child psychiatrist specializing in ADHD and autism, and a professor emeritus at Ohio State University, said Friday that although he hadn't yet drafted his testimony for next week's hearing, he felt there were many scientific issues to be clarified. For example, he said the Southampton researchers looked at combinations of food colorings and preservatives, so it's unclear which could have been responsible for observed effects.
"We don't know if it's a mix of food dyes, or whether there's one or two particular ones causing the problem and others maybe aren't doing anything," he said in an interview from his office at Ohio State.
Although Arnold officially will testify on behalf of the patient group Children and Adults with Attention Deficit/Hyperactivity Disorder (CHADD), he said that speaking purely for himself, he had devised an easy rule of thumb: "If something is safe, easy, cheap and sensible to do, you don't need as much evidence to take action. In this case, the action would be to remove artificial food dyes from foods targeted to kids."
"Dyes are not an essential food group," he said. "We have an obesity epidemic; it's not necessary to make food more attractive. The sole purpose of the dyes is to make food more attractive."
Unlike preservatives, which keep food from spoiling, "there's certainly no risk to taking it away. Until we have better research to really tease out what's going on here, it would really make sense to really stay away from the artificial food dyes."
Among others scheduled to testify next Wednesday and Thursday are Jacobson; Andrea Chronis-Tuscano, associate professor and director of the University of Maryland ADHD program; and Sean Taylor, scientific director of the International Association of Color Manufacturers.
In anticipation of the FDA advisory panel hearing, the International Food Information Council Foundation, a non-profit, educational arm of the International Food Information Council, which represents an array of food, beverage and agricultural industries, posted background on its website that said questions about a connection between artificial colors and hyperactivity had been raised "by a small subset of the scientific community." It suggested that people who want to avoid food colors "either due to preference or because of a suspected food sensitivity can do so by simply reading the label and avoiding those products. Likewise, consumers who are not affected can still consume foods containing food colors without feeling concerned about their approval for food use, safety, or role in child hyperactivity."
According to the National Institutes of Health, ADHD affects 3 percent to 5 percent of all American children. In addition to being hyperactive, children and adults with ADHD may also suffer from inattention and impulsivity.