Latest literature data for effects and risks of gluten-free diet in autism with or without its combination with other diets

General Medicine, 2025, 27(6), 40-46.

D. Marinov, R. Pancheva

Department of Hygiene and Epidemiology, Faculty of Public Health, Medical University “Prof. Dr. Paraskev Stoyanov” – Varna

Abstract. This literature review examines the effects of gluten-free and casein-free diets in children with Autism Spectrum Disorders (ASD). These diets are popular among parents based on the theory of elevated levels of opioid peptides (exorphins) in children with autism, potentially disrupting brain function and behavior. A systematic search was conducted in PubMed, Scopus, Web of Science, and Cochrane Library databases from 2000 to 2024, using keywords such as “autism spectrum disorder,” “gluten-free diet,” “casein-free diet,” “behavioral outcomes,” and “gastrointestinal symptoms.” The analysis included 10 randomized clinical trials and several systematic reviews. Findings indicate limited and conflicting evidence regarding the benefits of these diets on autism symptoms, cognitive abilities, and gastrointestinal symptoms. Methodological limitations include small sample sizes, short study durations, lack of objective biomarkers, and excessive reliance on subjective parental assessments. Current evidence does not support the routine use of gluten-free or casein-free diets in children with ASD, except in specific medical conditions such as celiac disease or food allergies. Future studies with improved design are necessary to clarify the potential benefits and risks of these dietary interventions.

Key words: autism, gluten-free diet, casein-free diet, exorphins, behavioral symptoms, gastrointestinal symptoms

Address for correspondence: Chief Assistant Professor Dimitar Marinov, MD, e-mail: dr.marinov.md@gmail.com