Description: Alteration of the participant’s food intake for the purpose of changing behavior. Many diets involve eliminating substances from the participant’s food intake.
Examples: Gluten-Free (wheat), Casein-Free (dairy), Sugar Free, Removal of food dyes, Foods thought to produce maladaptive behavior
Research Summary: Two well-designed but small studies found no evidence of benefit from the gluten-free, casein-free (GfCf) diet (Elder et al., 2006; Hyman et al., 2016).
Additional study of the theoretical basis and efficacy of the GfCf diet is warranted (Millward, Ferriter, Calver, & Connell-Jones, 2008). There is a risk that removing gluten and casein from an individual’s diet will lead to inadequate nutrition; therefore, dietary counseling is important for families who place their children on the diet (Hyman & Levy, 2015).
One study with substantial methodological limitations found that camel’s milk did not differ from cow’s milk in its effect on behavior (reviewed by Williamson et al., 2017).
There are no scientific studies on other dietary interventions for children with autism spectrum disorders.
Recommendations: An important area for research is to conduct studies with strong scientific designs to evaluate the GfCf diet and other dietary interventions for individuals with autism spectrum disorders. Professionals should present diets as untested as a treatment for autism spectrum disorders, recommend dietary counseling to ensure adequate nutritional intake, and encourage families who are considering this intervention to evaluate its effects and side-effects carefully.
Selected scientific studies:
Hyman, S. L., Stewart, P. A., Foley, J., Peck, R., Morris, D. D., Wang, H., & Smith, T. (2016). The gluten-free/casein-free diet: a double-blind challenge trial in children with autism. Journal of Autism and Developmental Disorders, 46(1), 205-220. doi: 10.1007/s10803-015-2564-9
Elder, J. H., Shankar, M., Shuster, J., Theriaque, D., Burns, S., & Sherrill, L. (2006). The gluten-free, casein-free diet in autism: Results of a preliminary double blind clinical trial. Journal of Autism and Developmental Disorders.
Systematic reviews of scientific studies:
Levy, S. E., & Hyman, S. L. (2015). Complementary and alternative medicine treatments for children with autism spectrum disorders. Child and Adolescent Psychiatric Clinics of North America, 24(1), 117-143.
Millward, C., Ferriter, M., Calver, S., & Connell-Jones, G. (2008). Gluten- and casein-free diets for autistic spectrum disorder. The Cochrane Database of Systematic Reviews, 2, Cd003498
Williams, K. E., & Foxx, R. M. The Gluten-Free, Casein-Free Diet. In R. M. Foxx & J. A. Mulick (Eds.) (2016). Controversial Therapies for Autism and Intellectual Disabilities: Fads, Fashion and Science in Professional Practice. (pp. 410-421). New York, NY: Routledge.
Williamson, E., Sathe, N. A., Andrews, J. C., Krishnaswami, S., McPheeters, M. L., Fonnesbeck, C., … Warren, Z. Medical Therapies for Children With Autism Spectrum Disorder—An Update. Comparative Effectiveness Review No. 189. (Prepared by the Vanderbilt Evidence-based Practice Center under Contract No. 290-2015-00003-I.) AHRQ Publication No. 17-EHC009-EF. Rockville, MD: Agency for Healthcare Research and Quality; May 2017. doi: 10.23970/AHRQEPCCER189.
Harrison K. L., & Zane, T. (2017). Is there science behind that? Gluten-free and casein-free diets Science in Autism Treatment, 14(2), 32-36.