RT Journal A1 WENDER EH T1 MOre on food additives and hyperkinesis-reply JF American Journal of Diseases of Children JO American Journal of Diseases of Children YR 1979 FD October 1 VO 133 IS 10 SP 1081 OP 1081 DO 10.1001/archpedi.1979.02130100104027 UL http://dx.doi.org/10.1001/archpedi.1979.02130100104027 AB In Reply.—Dr Crook accurately summarizes Swanson's preliminary report, but two features of the study suggest a cautious interpretation of the results:The first issue is the dose of food coloring mixture that should be used in challenge studies. Proponents of the Feingold diet have stated that negative findings in controlled studies result from the use of an inadequate dose. The challenge food bar prepared under the supervision of the Nutrition Foundation contains 13 mg of a food-coloring mixture. This dose was calculated by dividing the average daily consumption of food coloring in the United States by the total population, yielding a figure of 26 mg. Since food colorings are not ingested in one large bolus, the amount contained in each food bar was arbitrarily set at one half that dose. In most studies, two food bars were taken daily, with a time interval of four hours between doses. Since