For some children with an autism spectrum disorder (ASD), a gluten-free, casein-free diet leads to improvements in behavior and physiological symptoms, according to researchers at Penn State.
This the first study to draw on survey data from parents recording the use of a gluten-free, casein-free diet on children diagnosed with ASD.
“Research has shown that children with ASD commonly have GI [gastrointestinal] symptoms,” said Christine Pennesi, medical student at Penn State College of Medicine.
“Notably, a greater proportion of our study population reported GI and allergy symptoms than what is seen in the general pediatric population. Some experts have suggested that gluten- and casein-derived peptides cause an immune response in children with ASD, and others have proposed that the peptides could trigger GI symptoms and behavioral problems.”
For the study, 387 parents or primary caregivers of children with ASD completed a 90-item online survey reporting their child’s GI symptoms, food allergy diagnoses, and suspected food sensitivities, as well as how often the child adhered to a gluten-free, casein-free diet.
For those children with GI and allergy symptoms, a gluten-free, casein-free diet was more effective in improving ASD behaviors, physiological symptoms and social behaviors compared to children without these symptoms.
Specifically, when a gluten-free, casein-free diet was strictly followed, parents witnessed an improvement in GI symptoms in their children as well as improvements in social behaviors, such as language production, eye contact, engagement, attention span, requesting behavior and social responsiveness.
Autism may be more than a neurological disease, says Laura Cousino Klein, associate professor of bio-behavioral health and human development and family studies—it may involve the GI tract and the immune system.
“There are strong connections between the immune system and the brain, which are mediated through multiple physiological symptoms,” Klein said. “A majority of the pain receptors in the body are located in the gut, so by adhering to a gluten-free, casein-free diet, you’re reducing inflammation and discomfort that may alter brain processing, making the body more receptive to ASD therapies.”
Furthermore, when all gluten and casein was removed from the diet, parents reported that a greater number of ASD behaviors, physiological symptoms and social behaviors improved in their children compared to those whose parents did not eliminate all gluten and casein. Also, parents who implemented the diet for six months or less reported that the diet was less effective in reducing ASD behaviors.
Some of the parents had eliminated only gluten or only casein from the diet, but survey results suggested that parents who completely eliminated both gluten and casein reported the most benefit.
“While more rigorous research is needed, our findings suggest that a gluten-free, casein-free diet might be beneficial for some children on the autism spectrum,” Pennesi said. “It is also possible that there are other proteins, such as soy, that are problematic for these children.”
Klein said, “Gluten and casein seem to be the most immunoreactive. A child’s skin and blood tests for gluten and casein allergies can be negative, but the child still can have a localized immune response in the gut that can lead to behavioral and psychological symptoms. When you add that in with autism you can get an exacerbation of effects.”
“If parents are going to try a gluten-free, casein-free diet with their children, they really need to stick to it in order to receive the possible benefits,” she continued. “It might give parents an opportunity to talk with their physicians about starting a gluten-free, casein-free diet with their children with ASD.”
The study is published in the journal Nutritional Neuroscience.
Source: Penn State