With Autism, Diet Restrictions May Do More Harm Than Good
Study finds no increase in gastrointestinal problems in kids with the disorder
By Amanda Gardner, HealthDay Reporter
MONDAY, July 27 (HealthDay News) — Children with autism do not have a
higher incidence of gastrointestinal problems than other children, a
new study has found.
However, autistic children do have a higher rate of constipation and
eating issues, such as eating the same foods over and over, according
to the study. But any number of factors, including medication, could
cause these issues, the researchers said.
The findings appear in the August issue of Pediatrics.
Dr. Patricia Manning-Courtney, medical director of the Kelly O’Leary
Center for Autism Spectrum Disorders at Cincinnati Children’s Hospital
Medical Center, said that the study is an important one because it was
the first to scientifically compare the incidence of gastrointestinal
(GI) problems in an autistic population with incidence in children who
are developing normally.
Even so, it’s unlikely to quell a controversy that has been raging for
more than a decade.
“A couple of highly publicized cases of autism and loose stools in the
late 1990s led to an impression that children with autism had a higher
rate of GI dysfunction, ” she said. “It wasn’t well characterized, but
that got the story onto the national scene.”
This, in turn, led to theories that diets free of gluten and the milk
protein casein might help the problems, along with treatment with the
hormone secretin. Some even proposed that problems with the gut might
be the cause of autistic symptoms, giving the matter added urgency.
But the evidence in favor of these hypotheses was “fuzzy,”
Manning-Courtney said.
For the new study, researchers followed 124 children with autism and
248 children without autism until they turned 18.
Gastrointestinal diagnoses were classified into five groups:
constipation; diarrhea; abdominal bloating, discomfort or
irritability; gastroesophageal reflux or vomiting; and feeding issues
or selectivity (people with autism often stick with the same food
choices and have other “ritualistic tendencies” in eating).
The frequency of GI symptoms was about 77 percent in the autism group
and 72 percent among the others, not considered a statistically
significant difference.
However, almost 34 percent of the autistic children, compared with
nearly 18 percent of the others, had constipation. Feeding issues were
present in about 24 percent of the autistic children and 16 percent of
those who weren’t autistic, the study authors found.
Those differences could stem from what the researchers called
neurobehavioral issues connected with autism, such as the ritualistic
practices, they said.
“Many patients with autism insist on eating the same thing and might
not consume enough fiber,” said the study’s lead author, Dr. Samar H.
Ibrahim, a fellow in gastroenterology and instructor in pediatrics at
the Mayo Clinic. “We think this may be contributing to the
constipation. ”
Medications that autistic children take can also interfere with
appetite and eating.
“In our study, around 50 percent of children were on stimulant
medications, and those might affect appetite and might have something
to do with issues with food,” Ibrahim said.
Keith A. Young, vice chairman for research in the psychiatry and
behavioral science department at Texas A&M Health Science Center
College of Medicine, said he thought “the really interesting thing
they found was that there wasn’t any indication of celiac disease.”
In the group studied, the researchers found just one case. A possible
link between celiac disease and autism was proposed as far back as 1961.
“The only difference [between the two groups] was the constipation,
which they kind of dismiss,” Young said. “And I tend to agree with
their conclusion that constipation might be related to the dietary
habits of autistic kids.”
The constipation and feeding difficulties identified in the study,
though, are not the symptoms that people have been buzzing about,
Manning-Courtney pointed out. It’s mostly been about diarrhea and
loose stools.
But the study was a small one and did not rely on rigorous,
comprehensive diagnoses of autism for the participants, so it may just
stir the pot for people on both sides of the debate.
The researchers, however, are urging parents away from restrictive diets.
“Patients with autism should be investigated the same way as normal
patients when they have GI symptoms,” Ibrahim said. “And doctors
should do a thorough investigation before labeling them with any GI
disorder because the overall incidence of any GI disorder did not
differ from that of the overall population.”
Manning-Courtney concurred. “For me, this study lends support to the
recommendation I make to a lot of families that there is no evidence
to support restricted diets,” she said. “They’re dangerous and risky.
You have to think long and hard before you, as a parent, make that
choice.”
