Gluten’s Role in Autism

in Celiac
Published: October 23, 2012

To prove his theory, Fasano needs tests on a much larger scale. And that’s why, 15-odd years after first meeting that 5-year-old boy, he is a lead scientist in two studies that are exploring the links between general gastrointestinal dysfunction and ASD.

Investigators from the Celiac Disease Center, the University of California at Davis and the California Institute of Technology are now studying the biological makeup of the guts of children with ASD. They’ll try to confirm the suspected biomarkers of gluten sensitivity in these kids and, if successful, they’ll put the kids with those biomarkers on gluten-free diets. Then they’ll observe, to see what happens to their symptoms.

In the second study, the scientists are working with mice – which are given genes that make them behave in a manner akin to autism. The researchers will use these mice to test a therapy that bombards the gut with probiotics. The idea is to figure out the role of microorganisms involved in gluten sensitivity and, ultimately, their role in ASD. If successful, this could lead to a non-medicinal therapy that involving probiotics and gluten-free diets.

There is so much confusion surrounding ASD. Fasano has tallied up more than 50 treatments being practiced that are either scientifically unproven or debunked. They range from the prescribing of antidepressant drugs to enclosing kids in hyperbaric chambers, foregoing vaccinations for common childhood diseases and chelation – the removal of heavy metals from the body.

“Amongst all these treatments, adjusting a diet so it does not contain certain elements seems the most innocent of all,” he says. “But there should be scientific research to back up such a decision.”


The stakes for research success are high, since at least one in 110 children in the United States is thought be on the spectrum, and living with its profound effects. That’s a staggering 600 per cent increase over the past two decades, with treatment and support costs in the United States alone running beyond $35 billion a year.

Improved diagnoses can only partly explain the ASD phenomenon. For years, autism was only considered a neurological condition (or conditions), but then scientists like Dr. Stanley Finegold of UCLA began studying the role of the gut and gut bacteria.

Today, Fasano and his colleagues are moving that research forward to a related but different question: might it not just be the gut, but a “leaky gut” that explains at least a significant part of this disordered spectrum?

Fasano is exploring the links between a genetic predisposition for ASD, environmental triggers such as nutrients and “leaky gut syndrome,” which he knows occurs in celiac disease and, he suspects, also in gluten sensitivity.

The syndrome occurs when the body detects gluten and releases zonulin, a protein which makes the intestine more permeable or “leaky”, allowing certain molecules, including gluten, the dairy protein casein and other proteins to pass through the cells that line the intestines. This leads to an immune response and gut inflammation.

Fasano ascribes to a theory that some inflamed cells in the gut make it through the bloodstream to the brain, causing ASD in the group of children with the genetic predisposition.

At least half of kids on the spectrum are thought to have some kind of gastric issue. But like that early patient of Fasano’s, many of the children do not speak, which leads them to express distress in other ways. Some will scream or whine, some are frequent throat-clearers, others eat constantly, while still others can’t sleep through the night. And many parents, desperate for something, anything that might help, place their children on diets free of gluten and casein, even though the evidence to support this is only anecdotal.

It is time to change that, according to Dr. Clara Lajonchere, the vice-president of clinical programs for Autism Speaks, the world’s largest autism science and advocacy group which is funding one of the two new research studies. (The other is financed by the U.S. Department of Defense, which funds a number of initiatives linked to the health of military personnel and their families, including autism.)

Scientists need to sift through the often passionate testimonials and tales, says Lajonchere, to prioritize the issues for families and to rigorously test, measure and weigh the benefits of alternative treatments against those of traditional medicine.

Next page: Shedding light and moving to treatment