Diet and hyperactivity: Is there a relationship?

The Feingold hypothesis on the relationship of hyperkinesis in children to dietary factors, particularly salicylates and artificial colors and flavors in foods, has been tested in many cases and experiments. Feingold reported that strict adherence to the K-P diet resulted in dramatic improvement in 40-70% of his cases, based on clinical observations. Other researchers have evaluated the diet's effectiveness using diet crossover studies and specific challenge experiments, with conflicting results. Studies at the U. of Pittsburgh appeared first to support Feingold's theory, then refute it. Results of U. of Wisconsin research based on parent, teacher, and observer ratings, neuropsychological tests and laboratory observations, showed that only parents saw a significant improvement in children's behavior. More recent information indicates that most of the children who do respond to the K-P diet do not respond to challenges, indicating that some factor other than food additives and salicylates is responsible for improvement in children's behavior