THURSDAY, Feb. 3 (HealthDay News) -- A special restrictive diet
may significantly reduce symptoms of attention-deficit
hyperactivity disorder (ADHD) in young children, a new study
When children between the ages of 4 and 8 were placed on a diet
containing no processed foods for five weeks, ADHD symptoms
diminished in 78 percent of them. And, when suspected trouble foods
were reintroduced into the diet, two-thirds of the children
experienced a relapse in symptoms.
"A strictly supervised restricted elimination diet is a valuable instrument to assess whether ADHD is induced by food," wrote the study authors. "We think that dietary intervention should be considered in all children with ADHD, provided parents are willing to follow a diagnostic restricted elimination diet for a five-week period, and provided expert supervision is available," they concluded.
Results of the study are published in the Feb. 5 issue of
ADHD is a common childhood disorder, according to the National
Institute of Mental Health (NIMH). Children with ADHD have trouble
paying attention, focusing and can be hyperactive. Parents have
long suspected that sugary foods might be a culprit in inducing
symptoms, but there's not a lot of evidence to support this theory,
according to the NIMH. However, food additives and preservatives
have recently been singled out as possibly having an effect on
children's behavior, though the evidence isn't yet conclusive.
Since some children have negative physical reactions to certain
foods -- such as eczema, asthma and gastrointestinal problems --
that affect different organ systems, it has been suggested that
foods may also affect the brain in a way that results in adverse
behavior, according to information in the study.
To test this theory, the researchers recruited 100 children from
Belgium and the Netherlands. The children were between the ages of
4 and 8, and all had been diagnosed with ADHD. Most of the children
The children were randomly assigned to one of two groups. One
group was placed on the restrictive elimination diet, and the other
group served as a control group and received advice on healthy
The restrictive diet began with a diet called the "few foods
diet," which includes just rice, meat, vegetables, pears and water.
The researchers then complemented this diet with certain foods,
such as potatoes, fruits and wheat. The restrictive diet lasted for
During the next four weeks, kids in the restricted diet group
received two food challenge diets, in which certain foods were
reintroduced into the diet. The researchers selected foods that
were considered both low- and high-IgG foods.
IgG is an antibody made by the immune system that some
alternative medicine practitioners believe is linked to food
hypersensitivities; however, IgG testing is controversial among
many mainstream physicians and even some naturopaths, according to
background information in the study.
Some complementary medicine practices test for IgG and recommend
eliminating foods high in IgG, explained Dr. Jaswinder Ghuman, who
wrote an accompanying editorial in the same issue of the
Forty-one children completed the restrictive phase of the diet.
Of those, 78 percent had a reduction in their ADHD symptoms,
compared with no improvement in the controls. Nine children (22
percent) didn't respond to the diet. On an ADHD symptom scale that
ranges from 0 to 72 points, with a higher score indicating more
severe symptoms, the average reduction was 24 points, according to
Thirty children who had shown a response on the restrictive diet
went on to the challenge test. Nineteen of those children had a
relapse in symptoms on the challenge test. What's more, it didn't
appear to matter if the children with challenged with a low- or
"Measuring IgG levels in kids doesn't seem helpful," Ghuman said, but it does look as if the elimination diet may help some children.
"If parents have noticed that a child's behavior seems to get worse with certain foods, it may be worth considering," said Ghuman, who is an associate professor of psychiatry and pediatrics at the University of Arizona in Tucson.
"But, for this diet to work, you have to be very consistent with it, and you have to pay attention to nutrition. It should be done under the supervision of a primary care doctor, and if possible, a dietician," she advised.
Ghuman said that this study doesn't answer a number of
questions, such as whether or not the elimination diet reduces
symptoms long-term. And, she added, that clinical practice
shouldn't be changed based on the results of one study.
Dr. Andrew Adesman, chief of developmental and behavioral
pediatrics at the Steven and Alexandra Cohen Children's Medical
Center of New York in New Hyde Park, echoed Ghuman's concerns.
"Since none of the children stayed on the diet beyond five weeks, it is hard to know if this dietary intervention offers sustained benefit," he said, adding, "Since it is more difficult to enforce restricted diets in older children, this approach may not be suitable for the majority of older children with ADHD."
Adesman also pointed out that this study is only applicable to
children with ADHD, not to children who had ADD without the
Learn more about ADHD from the
National Institute of Mental Health.