The Lancet will soon publish the results of the 'Impact of Nutrition on Children with ADHD (INCA)' study. This is yet another, very well done, study on elimination diets and ADHD. The results of this study reported two findings.

The first finding was that a strict elimination diet improved symptoms of hyperactivity, impulsive behavior, oppositional behavior and inattention. The second finding was that the benefits in these behaviors did not correspond to an increase in blood IgG levels (a blood measure of an allergic reaction) in the kids that had behavioral changes. The second finding is interesting because it shows us that testing for IgG will not always tell us that a child has a food allergy.

Of the 41 (82%) of 50 children in tested the restricted diet group, 32 (78%) had improved behavior as measured by both questions and pediatrician evaluation. Thirty of the kids that had improved improved symptoms on the very restricted diet were then 'challenged' with foods such as chicken egg, peanut, soy, milk, fish, and wheat. Nineteen of the thirty, 63%, had a relapse of symptoms.

If we go back to the original number of 41 kids we see that almost half of them seemed to have symptoms that improved when they did not eat certain foods and worsened when they ate them. This study involved different individual diets for each participant but all children started on a diet of nothing but rice, meat, vegetables, pears, and water, the diet lasted 5 weeks and was sometimes complimented with potatoes, fruits, and wheat.

The elimination diet is one of the few treatment that has been shown in a clinical trial to markedly improve Oppositional Defiance Disorder. Given that this ADHD co-morbidity is especially disrupted to families and schools, the findings of this study may be the answer that many parents and teachers have been longing for.

As is often the case in the study of Inattentive ADHD, the measures that the researchers looked at to gauge improvement in attention were not as accurate as the measures taken for the symptoms of impulsive behavior, oppositional behavior or hyperactivity. It is therefore not clear from this study how much benefit was derived from the restricted diet with regards to improving attention.

The recommendations that the authors give at the end of this study differ obviously from current medical recommendations. The study recommendations are a radical departure from the manner in which pediatrician and psychiatrist have viewed a child's diet, and it's role in symptom control, in the past. What they recommend is that ALL kids with ADHD should FIRST be treated with a psychiatric intervention and only if this does not help should behavioral therapy and drug therapy be initiated.

This is what they say, in their own word. “Our study shows reasonable effects of a restricted elimination diet in children with ADHD, with equal effects on ADHD and oppositional defiant disorder. diet should be diagnosed with food induced ADHD and should enter a challenge procedure, to define which foods each child responds to … In children who do not show behavioral improvements after following the diet, standard treatments such as drugs, behavioral treatments, or both should be considered. ”

These findings tell us that diet can help the symptoms of ADHD but the authors, while suggesting the same treatment, different from the most popular elimination dietories. The most popular theories regarding the success of eliminationd diets claim that it is artificial dyes and preservatives that are the causes of ADHD behavior in children. If I am understanding the study findings, the authors disagree. These researchers believe that certain foods cause kids to have sensitivities of reactions to them and that these food may be foods that are, not necessarily, full of artificial ingredients. The INCA reseachers contend that it is the proteins and other components of these 'allergy causing' foods that cause a particular child to be sensitive to it and this is what causes the hyperactivity, oppositional behavior or other attention behavior behavior.

Elimination diets can help the symptoms of ADHD and may be the first line of treatment for many children and adults that have symptoms of hyperactivity, inattention, impulsive behavior and oppositional behavior. Parents and patients should always check with their doctors before initiating any diet program.