Parents with autistic kids often go to great lengths to help their children develop their social skills and improve their ability to communicate. They might work with them for hours every day or pursue little-known but potentially promising therapies dismissed by the medical mainstream. Some put their children on a gluten- and casein-free diet, on the theory that their children have gastrointestinal problems that can be eased by a food regimen free of wheat and milk proteins.
Now actress Jenny McCarthy has written a book extolling the benefits of such a diet. Following the regimen isn't easy -- eliminating gluten and casein is quite difficult. Gluten is found in a plethora of food products, including bread and soy sauce, and casein is a staple of milk, yogurt and everything else made from milk. But the diet dramatically helped her own son, McCarthy says, explaining that the number of words he knew doubled after being put on such a diet.
Her celebrity status is likely to lend credence to the diet as an autism treatment, but most health experts say there is no good evidence that supports its use in autistic children. "Even if autistic kids have gastrointestinal problems, it certainly doesn't warrant a knee-jerk response to go on a gluten- and casein-free diet," says Dr. Raun Melmed, a pediatrician with the Scottsdale, Ariz.-based Melmed Center, which provides services for children who have developmental disorders.
A 2002 study of 600 children registered with the General Practice Research Database in the United Kingdom found that at the time of diagnosis, the percentage of autistic children with gastrointestinal disorders was the same as in healthy children of the same age. "There doesn't seem to be that kind of gut problem," says experimental psychologist and autism researcher William Ahearn of the New England Center for Children in Southborough, Mass.
But a 2006 study of 50 autistic children in New York who were compared with healthy children of the same age and sex, found that autistic children were more than twice as likely to have GI problems by age 7 than their healthy peers. A large study led by researchers at the University of Rochester is in progress to address whether a gluten- and casein-free diet helps autistic kids; results are expected next year.
Ahearn says children who have developmental disorders such as autism do get more constipation and diarrhea than do other kids, probably as a result of not being potty trained as easily. "Just like every other developmental marker, they're behind," Ahearn says. But he worries that because autistic children are already pickier eaters than healthy children, they might not get the nutrition they need on the diet.
With results from the Rochester research still out, the stories of parents with autistic children who seem to improve on a gluten- and casein-free diet proliferate. Ahearn points out that the children might be improving because the parents are using proven interventions, such as intense behavioral therapy, along with keeping their children on a special diet. "If you do everything at once, and the kid gets better, what are you going to attribute it to?" he asks. "All the hard work the parents put in -- are the children learning new skills because they're being taught?"
But many parents and some autism experts say the diet works. Researcher Stephen Edelson of the Center for the Study of Autism in Salem, Ore., says autistic children often have gastrointestinal tracts that let nutrients slip through unabsorbed or other digestive problem. Some proponents of the diet theorize that the small proteins in wheat and dairy products slip out of the GI tract and head to the brain, where they mimic morphine and cause brain damage. Melmed says the evidence for that theory is shaky, and adds that parents should continue proven interventions -- regardless of whether they try unproven ones.