Context: It has been suggested that a gluten-free and casein-free (GFCF) diet may alleviate the symptoms of autism spectrum disorder (ASD) and facilitate neurodevelopment of children with ASD. Studies to date have been inconclusive.
Objective: This study aimed to evaluate (through quantitative meta-analysis) the efficacy and safety of a GFCF diet for children with ASD. To our knowledge, this is the first time such an analysis has been carried out.
Data sources: Eight electronic databases were searched, from the establishment of each database up to March 27, 2020: PubMed, Web of Science, Embase (Ovid), PsycINFO (Ovid), Cochrane Library, CNKI, Wanfang, and VIP databases.
Data extraction: Two authors independently performed the data extraction and risk-of-bias assessment.
Data analysis: A quantitative meta-analysis was performed with standard procedures by using Stata SE 15 software. Within the total of 8 studies, with 297 participants, 5 studies reported significant reductions in stereotypical behaviors [standard mean difference (SMD) = -0.41, 95% confidence interval (CI): -0.68 to -0.15], and 3 studies reported improvements in cognition (SMD = -0.46, 95% CI: -0.91 to -0.01) following GFCF dietary intervention . No statistically significant changes were observed in other symptomatic categories (all P > 0.05).
Conclusion: The current meta-analysis showed that a GFCF diet can reduce stereotypical behaviors and improve the cognition of children with ASD. Though most of the included studies were single-blind, the benefits of a GFCF diet that have been indicated are promising. Additional studies on a larger scale are warranted.
Systematic review registration: PROSPERO registration no. CRD42020177619.
Keywords: autism spectrum disorder (ASD); dietary intervention; gluten-free diet and casein-free diet (GFCF); meta-analysis.
© The Author(s) 2021. Published by Oxford University Press on behalf of the International Life Sciences Institute.