Leo Galland, MD, Director of the Foundation for Integrated Medicine, wrote in a Sep., 1999 article titled "ADHD," published in Better Nutrition:

“[A] study was done at the Hospital for Sick Children in London and published in the leading British journal, Lancet, which demonstrated that most children with severe ADHD are salicylate [plant-based hormone] sensitive, but that 90 percent of these children have additional food intolerances… After determining that 80 percent of the children had apparent food sensitivities as a cause of hyper activity, they then performed double blind, placebo controlled challenges with the offending foods. Using this most rigorous clinical research method, the investigators confirmed the presence of food intolerance in the majority of children with ADHD. Subsequent research by the leading investigator of this study suggested that these food intolerances represent true food allergy. The foods to which children with ADHD most commonly had allergic reactions were cow’s milk (which included milk, cheese, yogurt and ice cream), corn (an additive in many prepared foods), wheat, soy, and eggs… In my clinical practice I have found that food allergy is especially likely to be implicated in ADHD.”

Sep. 1999