A restrictive diet may help some children with attention deficit hyperactivity disorder (ADHD) improve their behavior, according to a new study.
In the study, about three-quarters of children with ADHD on the diet were found to be less hyperactive and impulsive than children not on the diet, the researchers said.
Some improved so much that that "they wouldn’t satisfy anymore the criteria for ADHD," said study researcher Jan Buitelaar, of the Radboud University Nijmegen Medical Centre in the Netherlands. The diet might allow a large number of children to avoid taking ADHD medications , he said.
The diet — which consists mainly of water, white meat, rice and vegetables — is not for everyone. Some children in the study did not improve at all. Though experts are intrigued by the study, they warn restrictive diets may bring about more behavioral problems — children may battle with their parents for food they cannot have, said Dr. Dorothy Stubbe, an associate professor at Yale University School of Medicine's Child Study Center in New Haven, Conn.
"I think if we can do things to help kids we should, but I'm not convinced that restricted diets should be generally implemented," she said.
She said dietary measures may be used in addition to behavioral treatments, educational interventions and medication, "but I don’t think any of those alone would be the preferred treatment," she said.
The study is published this week in the journal the Lancet.
The idea that foods with sugar, artificial colorings and added preservatives cause hyperactivity and are related to ADHD is a misperception, Buitelaar said. But it's possible that certain foods trigger an immune reaction that sets off ADHD symptoms, Buitelaar said.
The study involved 100 children ages 4 to 8. Half followed the diet for five weeks and half did not, but were provided with healthy diet advice . The children's parents, along with teachers and a pediatrician who did not know which children were on the diet, rated the children's behavior.
Of the 41 children who completed the diet, 32 responded to it — they were rated as having fewer behavior problems than children not on the diet.
When certain foods were added back to the diet, some children relapsed into their old behavior, the researchers said.
The diet should be considered for children with ADHD, and followed for a short time under expert supervision to see if the child responds, the researchers added. Some food restrictions can be lifted if they do not trigger symptoms.
The study researchers assumed that diet induces ADHD, said Dr. Josephine Elia, a psychiatrist at the Children's Hospital of Philadelphia who studies ADHD. The causes of ADHD are complex, and genetics is thought to be a large contributor . Other factors could explain the behavior changes, which the study could not account for, Elia said.
And because parents provided their children's food, they knew whether their children were on the diet. It's possible that expectations that the diet would work caused the parents to see their children's behavior more positively, Yale's Stubbe said.
Though a pediatrician also examined the children, "It is impossible to assess ADHD symptoms in a physician’s office," Elia said.
In addition, it is known that paying more attention to a child with ADHD can improve behavior. "I would assume that the children who were on the individualized tailored diets had to be monitored more closely than the other children," Elia said. She suspects it was the extra attention that led to the improvement.
Finally, the study was conducted for just five weeks. "It is not uncommon to get improvement for a few weeks, regardless of what treatment you implement," Elia said. "A longer time period is needed to assess whether a treatment is effective or not."
Pass it on: A restricted diet may help children with ADHD improve their behavior. However, more research is needed to verify the results and some children do not respond at all to the diet.
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