Feb. 3, 2011 -- Children with attention deficit hyperactivity disorder (ADHD) should be offered a special ADHD diet to see if eliminating certain foods might reduce their symptoms, Dutch researchers say.
The diet studied, known as the restricted elimination diet (RED), can work, the researchers say, because they believe ADHD symptoms in some children might be affected by eating specific foods.
''I am of the opinion that every child deserves this diagnostic intervention," researcher Lidy Pelsser, PhD, of the ADHD Research Centre in Eindhoven, the Netherlands, tells WebMD.
In the study, published in The Lancet, 78% of children who stuck with the diet did respond by having fewer symptoms.
In five weeks of trying the diet, Pelsser says, parents will know if their child is responding or not; if not, they can move on to other treatments.
U.S. experts had some caveats, saying that the results of the study, which included 100 children, should be repeated in other populations to see if the findings hold up.
ADHD affects about 3% to 7% of U.S. school-aged children, according to the American Psychiatric Association, but other sources put the figures higher.
The disorder is marked by inattention, hyperactivity, and impulsive behavior. Some children with ADHD also have oppositional defiant disorder (ODD), in which they express hostility and rebelliousness toward authority figures.
Experts aren’t sure of the cause of ADHD, but theorize that both genetic and environmental factors play a role. Specific foods or ingredients are thought by some to be linked to the symptoms. Besides dietary restriction, medication and behavior therapy are used to treat children with ADHD. In RED, foods that are thought to trigger symptoms are eliminated; the foods are reintroduced if they do not trigger symptoms.
Positive Response to ADHD Diet
Pelsser and colleagues assigned 100 children diagnosed with ADHD, ages 4 to 8, either to five weeks of the ADHD diet or to five weeks of following a healthy diet, with instructions on how to do so.
The ADHD diet was individualized for each child, eliminating foods that might cause problems. The diet was restricted to certain foods including rice, meat, vegetables, pears, and water, along with other foods such as potatoes, fruits, and wheat.
In the ADHD diet group, 41 of 50 children finished the first phase. In that group of 41 children, 32, or 78%, responded favorably by having fewer symptoms. Overall, 32 of 50, or 64%, responded favorably.
''Not only ADHD, but also ODD symptoms, characterized by stubbornness, temper tantrums, and provocative behavior, which were present in 50% of the children, decreased significantly," Pelsser tells WebMD.
When the offending foods were reintroduced, symptoms returned in those who had responded favorably, the researcher says.
While previous studies have found a link between foods and ADHD symptoms, the researchers say the studies were typically small or only included children known to have a tendency to allergies; their study is more applicable to the population as a whole.