The Link between Food Ingested and Problem Behavior: Fact or Fallacy?.

One prevailing conceptualization of negative behavior is that it can be linked to al lergic food reactions. Early historical examinations of food dyes and additives claimed that a link was evident. However, recent research has since shown no connection between food additives and adversive behavior. Past and current re search on the effects of foods ingested on hyperactivity and other negative behav iors is examined in this article. Methods for informing the public of the findings are discussed. Although the notion that food allergies directly cause behavior problems can be traced to the 1930s (Rowe, 1931), the link between food allergies and overt physical symptoms (e.g., rashes, swelling) was the primary focus of the early literature (Crook, Harrison, Crawford, & Emerson, 1961). As mental health professionals turned their attention to be havior and learning problems in children in the 1960s, there was renewed interest in the ef fects of food-based allergic reactions. However, the focus of this interest shifted from overt physical reactions to the effects of food on behavior (e.g., hyperactivity). This interest spread quickly. As stated by Conners, "The idea had a disarming simplicity and promised to reveal at one fell swoop both the causes of the problem and a simple method for its cure" (1980, p. 4). The Feingold Hypothesis Benjamin Feingold (1968) stated that a number of physical symptoms result from the inges tion of artificial flavors and colors. In addition, he began to examine the correlation between behavioral disturbances and these food additives. One of Feingold's first cases involved a woman treated for hives with a salicylate-free diet. Feingold claimed that the woman had not previously responded to 2 years of psychotherapy, yet her adverse behaviors disappeared following the administration of his diet (WOR Radio-TV Reports, The McCann Show, June 18, 1974). Shortly thereafter his attention turned to aspirin-allergic children whose hives and negative behaviors were treated — and allegedly cured — with his diet. He reported that within days a rapid and dramatic positive change in behavior resulted from the diet. The media aided in the proliferation of the idea of a connection between food and hyper activity. The Washington Post publicized Feingold's reports on October 29, 1973. Senator Glen Beall of Maryland, upon reading the news item in the newspaper, requested it be reprinted in the Congressional Record of the U.S. Senate on October 30, 1973. At a meet ing of the American Medical Association in early 1974, Feingold again suggested that food additives contributed to hyperactivity. This notion spread through the medical profession so rapidly that by September of the same year Feingold spoke on the topic in a symposium in London, England. By this time, the majority of the public were aware of the hypothesis that linked additives to hyperactivity. Feingold alerted the public to the fact that at that time there were more than 2,700 food additives (e.g., colors, flavors, sweeteners, preservatives) present in foods.. Specifically, over 80% of these additives were artificial colors and flavors that Feingold deemed carcino genic. Consequently, he concluded that such colors and flavors possessed an inherent po tential for producing adverse effects (Feingold, 1974). He claimed that adverse reactions to food additives had not been reported generally because people were naive to the connec tion between these substances and negative behaviors. 142 [Vol. 19 No. 2 142-148] February 1994 Behavioral Disorders This content downloaded from 157.55.39.45 on Wed, 05 Oct 2016 05:22:48 UTC All use subject to http://about.jstor.org/terms The additive that was primarily implicated by Feingold was a yellow dye known as tar trazine or FD&C No. 5. Those individuals allergic to acetylsalicylic acid were said to react adversely to this dye. Feingold also recommended that organic foods containing natural sali cylates be eliminated from the diets of those individuals with aspirin allergy. The resulting salicylate-free diet was later referred to as the Feingold (KP) Diet. Early reports of success of this diet were claimed to approach 50% of those exposed. As a means of defending the lack of success for half of these individuals, Feingold suggested a lack of adherence to the diet. Furthermore, he claimed that additives consumed during preg nancy could also account for the low effectiveness rate. Thus, failure was attributed to irre versible damage, sustained in utero when food additives crossed the placental barrier, af fecting the growing nervous system of the child (Feingold, 1975a, 1975b). Initially, there was very little skepticism regarding the validity of the effectiveness of the KP diet. Feingold's original findings were based on reports of mothers with hyperactive chil dren following the administration of the diet for a number of weeks. Feingold reported that children with learning disabilities and hyperactivity responded well to the elimination of addi tives. Further, he claimed that improvements were made in the areas of muscle coordina tion, writing, and speech abilities (Feingold, 1975a, 1975b). Testing the Feingold Hypothesis To test the Feingold hypothesis, Conners and colleagues (Conners, 1980) conducted a number of case trials on hyperactive children. The method was similar to that used by Feingold in that children were observed for several weeks both prior to and following the diet. The sole exception was that the children were also examined after discontinuing the diet. Whereas Feingold's trials were of simple A(treatment) B(efiect) design, Conners and colleagues utilized a more complex reversal (A-B-A-B) trial. Conners' studies were also more efficient due to the strict instructions provided and the concise records kept. In experiment one, the effects of the diet were measured by a behavior checklist (Conners, 1973) completed by the child's mother. Results indicated that mild improvement was noted following the commencement of the diet. By the second week of the diet, the mother reported a significant decrease in hyperactive symptoms. When the diet ceased, the symptoms increased, followed by a second treatment phase that replicated the initial posi tive behavioral effects. In contrast, a second experimental trial revealed an increase in neg ative behavior during both trials of the diet that the mother blamed on antibiotic medication. Being familiar with Feingold's hypothesis, she was aware that he linked artificial colors in medication to negative behavior. The authors suggested that this may have influenced her explanation. Due to limitations inherent in these uncontrolled clinical trials, Conners and his col leagues began controlled clinical trials with both examiners and participants blind to group assignment (Conners, Goyette, Southwick, Lees, & Andrulonis, 1976). In order to eliminate expectation biases, parents were led to believe that each diet (control and KP) was equally effective in the control of negative behavior. Unlike the Feingold trials, volunteers for this study were screened and had to meet a number of criteria for inclusion in the investigation. Along with age and IQ requirements, a diagnosis of Hyperactivity and Disorder of Attention Syndrome, as described by the National Institute of Mental Health (1973), was required. Both parents and teachers independently reported the child's behavior. Four weeks into the diet, each child and her/his parent(s) were interviewed regarding the effects of the diet. Based on the interviewers' ratings, only 4 of the 15 participants improved while using the KP diet. In contrast, teachers reported significant improvement while the children were on the KP diet. Ratings of behavior were significantly poorer while the child consumed the control diet. Parents' ratings reflected behavioral improvement with the KP diet, yet no clear behav ioral differences were found between the control and KP diet groups. The results of this study demonstrated that the dramatic improvements Feingold found in his work appear less impressive when the KP diet is used in comparison with a control diet. Due to the inconsistent findings, the National Advisory Committee on Hyperkinesis and Food Additives (1975) requested that researchers challenge those individuals who evi denced improvement on the Feingold diet with a food believed to cause adverse behavior. Behavioral Disorders February 1994 143 This content downloaded from 157.55.39.45 on Wed, 05 Oct 2016 05:22:48 UTC All use subject to http://about.jstor.org/terms The challenge method involved placing the subject on a diet excluding the food, and then reintroducing the food to examine possible reactions (Conners, 1980). The initial challenge study (Conners & Goyette, 1977) involved the administration to the child of additive-loaded foods at each Thursday mealtime. On Tuesday, Wednesday, and Friday, additive-free foods were provided for the child. Neither the child nor the parent(s) were aware of which foods contained the additives. The child's behavior was monitored by a researcher throughout each afternoon. Again, the results were inconsistent with children's behaviors appearing worse on the second challenge day than on the first. If adverse reactions occurred as a re sult of the additives, behaviors on both days should have been negative. Though strong anecdotal support existed at this time to support Feingold s position, scientific support was