Are Celiac Disease and Autism Related ?

Is celiac disease related to autism? Is autism related to celiac disease?

Autism is a highly complex disorder characterised by a series of symptoms including repetitive behaviours and poor social skills. Currently, it’s believed over 1% of children may fall within the autistic spectrum, from mild forms of Asperger Syndrome to more severe cases with learning disabilities. It’s known there is a strong genetic component – siblings of patients with autism have a higher risk of developing autism as well – but many environmental and immunological factors also play an important role.

Interestingly, gastrointestinal problems are a common complaint in children with autism. Speculation about gluten as a cause or at least contributor to autism (or other neuropsychiatric conditions such as schizophrenia) was proposed soon after the original description of autism in the early 1940s. Since then scattered references have appeared in the literature, suggesting a connection between nutritional factors and behavioural conditions. However, the actual link between celiac disease and autism remains a mystery.

Today, most physicians are inclined to say there isn’t any real association between the two conditions, with many studies to support this belief. For example, in 1997, Italian researchers found no connection between celiac disease and autism: their sample of patients with autism didn’t show a higher incidence for celiac disease and similarly, their group of patients with celiac disease did not have a higher proportion of cases of autism. More recently, researchers based at the University of Florida found similar results after a 12-week study in which autistic children received a gluten-free diet. In this case, the new diet did not help improve development or behaviour in any significant manner.

However, sometimes along comes a study that somewhat contradicts this view and opens up the question all over again. As an example, there are many clinical reports showing significant improvements in some autistic patients following a gluten-free diet. Also, recently Swedish researchers spotted a link between autism and positive blood tests for celiac disease.

Potential mechanism

Maybe due to these contradictory results, an explanation for this potential link is not immediately obvious. Attempting to find a reason, researchers seem to have excluded a genetic link, and instead speculate about increased intestinal permeability in some patients with autism. It could be this high permeability may allow for the absorption of short peptides that will eventually trigger the onset of celiac disease. Or, it could be that an increased permeability caused by celiac disease is an open door for compounds to cross the intestinal barrier, trigger an immune response and potentially cause autism. At the moment it is nothing more than speculation!

Whatever the mechanism, in practical terms, it would be ideal to be able to identify this group of patients, as they would greatly benefit from a gluten-free diet. It would not only improve digestive problems, but it would also stop absorption of undigested material, preventing an immune response and potentially improving symptoms both related to autism and celiac disease.