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, 36, 413-420.
Reviewed by Eric Rozenblatt, MA, BCBA
The gluten-free, casein-free diet (GFCF) requires eating foods that are free of wheat and milk. Many families report that their children with autism have shown improvements in communication, social development, and other aspects of functioning after starting the GfCf diet, and some claim their children have been “cured.” However, few scientific studies have been conducted to support (or refute) these claims.
Elder and colleagues evaluated the effects of the GFCF diet for 15 children with autism, including 12 boys and 3 girls between the ages of 2 and 16 years old. All children spent six weeks on a placebo diet containing gluten and casein and an additional six weeks on a diet that was truly gluten-free and casein-free. Half started on the placebo diet and then switched to the GfCf diet; the other half began on the GfCf diet before going on the placebo diet. The data manager and dietician provided all the foods to the children based on their preferences. The rest of the research team, the children, and their parents did not know when children were on the placebo diet and when they were on the GfCf diet.
The investigators conducted objective observations to see whether there was any difference in how frequently children interacted and communicated with others on the GfCf diet as compared to the placebo diet. They also examined whether the GfCf diet changed parent behaviors such as initiations of interactions and responses to the child. Finally, they tested whether the diet altered urinary peptide levels believed to be related to autism. Results showed no significant differences between the GfCf diet and the placebo diet on any of these variables.
Interestingly, even after being informed of these disappointing results, some parents opted to keep their child on the GfCf diet.
Based on the results of this study, we recommend that interventionists working with children with autism present the GfCf diet as non-supported as a treatment for autism and advise parents who are considering this intervention to evaluate it carefully.