The Effect of Gluten-Free Diet on Gastrointestinal Symptoms and Disease Severity of Autistic Children: A Randomized Controlled Trial GLUTEN-FREE DIET, GI SYSTEM AND AUTISTIC CHILDREN
Iranian Journal of Child Neurology,
Vol. 20 No. 2 (2026),
1 April 2026
,
Page 29-38
https://doi.org/10.22037/ijcn.v20i2.51043
Abstract
Objectives:
Autism Sspectrum Disorder (ASD) is a kind of neurodevelopmental disease characterized by difficulties in social interactions, verbal and non-verbal communication, movement limitations, and repetitive movement patterns. The goal of this study is to investigate the effects of a Gluten-Free Diet (GFD) on gastrointestinal (GI) and neurological symptoms in patients diagnosed with autism.
Materials & Methods:
In this study, 120 patients with autism from Tabriz Children’s Hospital and Sheikh Al-Rais Clinic were included. Neurologists and psychologists confirmed the diagnosis of autism using the M-CHAT-R/F questionnaire. Based on the patients’ clinical history and Rome 3 criteria, GI symptoms such as diarrhea, constipation, vomiting, and abdominal discomfort were detected. A Gluten Free Diet was advised, and the parents received nutrition education and ongoing autism therapies. The control group consisted of children who received specialized medications for autism while maintaining a regular diet. These children were monitored closely.
Results:
The average age of the patients was 9.27 ± 3.25 years with a median of nine years. Fifty-two patients (47.3%) were boys, and fifty-eight patients (52.7%) were girls. The severity of ASD, as measured by the M-CHAT-R/F scale, was significantly reduced at the 12th month in the intervention group. Furthermore, significant improvements in speech, cognition, and behavior have been observed in patients in the intervention group after using a GFD. Moreover, GI symptoms, including nausea and vomiting, constipation, abdominal pain, and discomfort, were significantly decreased in the intervention group. However, the GI symptoms in the control group did not show any statistically significant difference compared to the 12th month.
Conclusion:
According to the results obtained in this study, the administration of GFD in children with ASD can significantly lead to the improvement of GI disorders and neurological symptoms regarding the severity of autism in speech, cognition, and behavior.
- Autism Spectrum Disorder
- Diet, Gluten-Free
- Signs and Symptoms
- Digestive
How to Cite
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