The children did not demonstrate physical signs of hyperthyroidism. After treatment with the anti-thyroid medication neomercazole, a decrease in hyperkinetic behavior and an increase in attention span was noted in all three children. When medication was stopped in one child, the hyperactive behavior returned, and again diminished upon reinstatement of medication. Due to the improvement in behavior, all three were able to participate in speech therapy. Food additives are essentially anything that nature did not put in your food.
Examples are food colorings, preservatives, bleaching agents, thickeners, and anti- caking agents.
It is estimated that 8 to 10 pounds of food additives are consumed by each American every year. Feingold's work has created tremendous controversy in the past because many studies failed to support his observations. However, under closer scrutiny, these studies were faulty in terms of their design. As an example, one study compared a control group using chocolate cookies as a placebo. Additionally, cookies have ingredients and additives which may cause reactions according to Feingold's work.