Sir.—The relationship of diet to hyperactivity remains controversial. However, as pointed out recently in the Journal (132:1149, 1978) by Wender, "New findings... make the issue more complicated and should stimulate more careful research."
I am writing to briefly summarize a research report by James Swanson, PhD, of the Hospital for Sick Children in Toronto who gave a preliminary report on Oct 19, 1978, of an investigation he and Marcel Kinsbourne, MD, PhD, are conducting. He1 stated:
The present investigation departs in several ways from previous procedures. The most important change was a simple one; we increase the dose of color to 100 mg from the 13-mg amount recommended by the Nutrition Foundation (and used in most tests of the Feingold hypothesis).
With our revised procedures, we documented a relationship between the ingestion of this large amount of artificial color by our patients and a critical symptom of hyperactivity (impairment