Can Special Diets Treat Autism?
Review of Studies Shows Gluten-Free or Casein-Free Diets Aren't Effective as Autism Treatment
May 5, 2010 -- The use of gluten-free and casein-free diets to treat autism is increasingly popular among families, but researchers who reviewed 14 published studies on the diets say science does not back them up as useful.
"The evidence that has been collected does not support the use of the diets as a treatment for autism," study researcher Austin Mulloy, a doctoral student at the University of Texas at Austin, tells WebMD.
"A number of studies have been done and they are all inconclusive about the diets' effectiveness," he says. The review is published in the summer edition of Research in Autism Spectrum Disorders.
About one in 110 children in the U.S. has autism spectrum disorder, a group of neurodevelopmental disorders that include autism as well as Asperger's syndrome and other forms that involve difficulties in social relationships and communication.
Autism diets are quite popular, Mulloy says. Studies and surveys show that 17% to 27% of parents use a special diet to help treat autism or autism spectrum disorders.
Searching for the Cause of Autism
The cause of autism remains unknown; multiple genetic defects are thought to be involved in the disorder, along with an environmental trigger.
One theory suggests that some children have insufficient enzyme activity in their gastrointestinal tracts, resulting in incomplete digestion of the proteins casein and gluten. Casein is found in milk and other dairy products. Gluten is found in wheat, barley, and other grains.
In a normal GI tract, enzyme activity breaks down proteins into peptides and then into amino acids. When the gluten and casein aren't adequately broken down, the peptides derived from them can leak into the bloodstream and eventually travel to the brain, proponents of this theory say, resulting in the symptoms.
Parents who have put their children on the gluten-free, casein-free diets often post enthusiastic success stories on web sites, sometimes describing the changes as miraculous.
Reviewing the Evidence on Autism Diets
To test evidence about the diets, which Mulloy says can be expensive and time-consuming to follow, the researchers searched medical literature for scientific studies of the effectiveness of the autism diets.