The Gluten Free, Casein Free Diet by Katy Dorendorf, Psy.D.

The Gluten free, casein free diet, By Katy Dorendorf, Psy.D.

There is a significant increase in the use of the gluten free, casein free (GFCF) diet for individuals with ASD and a mounting interest due to recent media attention (Cormier & Elder, 2007). Gluten is a substance commonly found in cereal grains such as wheat, oats, barley, and rye while casein is a substance commonly found in cow’s milk (Cormier & Elder, 2007). The “opioid excess theory” is typically the rationale for implementation of a GFCF diet as a treatment for ASD (Knivsberg et al., 1990). Simply put, the opioid hypothesis proposes that dietary-supplied proteins are not being sufficiently broken down and the leftover fragments act like opioids in the brain and causing the symptoms observed in ASD (Knivsberg et al., 1990).


Initial research appeared to support the opioid hypothesis and indicated the GFCF diet decreased the presence of symptoms associated with ASD, increased positive development, and decreased the level of proteins observed in the urine of individuals treated with the diet (Reichelt et al., 1994). However, it is important to note early studies only included children with increased levels of peptides in their urine and they did not compare the children’s progress to children who were not being treated by the diet. Moreover, children continued to participate in conventional treatment programs while on the diet making it difficult to determine whether observed changes were the result of the diet alone or the other interventions they were receivingat the time (Knivsberg et al., 1990; Reichelt et al., 1994; Shattock et al., 1990).Conversely, results of a well-controlled trial, including children both with and without observable urine peptide levels, indicated no significant effects of the GFCF diet on behavioral measures or urinary peptide levels (Elder et al., 2006). Overall, it is important to note current research does not suggest the GFCF diet in any way “cures” autism, but rather that it may enhance traditional interventions and decrease discomfort and behaviors in children with a gluten and/or casein sensitivity.


The GFCF diet requires extensive time and monitoring to be implemented correctly. Additionally, children may resist the removal of such a large quantity of food choices from their diet. More financially relevant is that specialized foods included in the diet often cost considerably more than their gluten and casein containing counterparts.


Anyone attempting the GFCF diet with their child should be aware that some individuals may initially experience temporary symptoms such as itchy skin, rashes, restless behavior, sleep difficulties, and nutritional problems when starting the GFCF diet (Knivsberg et al., 1990; Reichelt et al., 1994). Children with ASD are especially at risk for nutritional problems because of common restricted eating patterns that can become more problematic after the elimination of foods from their diet. This can lead to nutritional deficiencies including decreased calcium and vitamin D, which is vital for a child’s growth and brain development, as well as essential amino acid deficits (Levy & Hyman, 2002). This is not to say a child cannot have a nutritionally adequate diet free of milk and wheat, but is simply meant to reinforce the essential need for nutritional consultation and monitoring by a qualified professional.

What you need to Know…

Gluten is found in many processed foods as well as Play-Doh, adhesives on stickers, and in many hygiene products. Casein is found in every dairy product and is even used as a binding agent in canned tuna fish, so children on the GFCF diet must avoid these products and many more. At school the child’s special education team will need to document that a dietary intervention is being used. Typically parents will be required to provide the GFCF supplies for their child to use in the classroom and any food that will be consumed over the course of the school day. Teachers and aides must ensure the child uses only the GFCF supplies and that food is not shared between students. Communication between families, educators, therapists, and doctors is critical as the GFCF diet can be extremely stressful to implement both at home and in the classroom.


Autism Speaks:

National Center for Complementary and Alternative Medicine (NCCAM):


Adams, L., & Conn, S. (1997). Nutrition and its relationship to autism. Focus on Autism & Other Developmental Disabilities,12(1), 53-59.

Cormier, E., & Elder, J. H. (2007). Diet and child behavior problems: Fact or fiction? Pediatric Nursing, 33(2), 138-143.

Elder, J. H., Shankar, M., Shuster, J. Theriaque, D., Burns, S., & Sherril, 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(3), 413-420.

Knivsberg, A., Wiig, K., Lind, G., Nødland, M., & Reichelt, K. L. (1990). Dietary intervention in autistic syndromes. Brain Dysfunction,3(5), 315-327.

Levy, S. E., & Hyman, S. L. (2002). Alternative/complementary approaches to treatment of children with autistic spectrum disorders. Infants and Young Children, 14(3),33-42.

Reichelt, K. L., Knivsberg A. M., Nødland, M., & Lind, G. (1994). Nature and consequences of hyperpeptiduria and bovine casomorphins found in autistic syndromes. Developmental Brain Dysfunction,7(2), 71-85.

Shattock, P., Kennedy, A., Rowell, F., & Berney, T. (1990). Role of neuropeptides in autism and their relationships with classical neurotransmitters. Brain Dysfunction, 3(5), 328-345.