Who Recommends Gluten Free and other Special Diets for Autism?

While mainstream doctors are unlikely to recommend special diets for children with autism, alternative doctors and practitioners may suggest gluten-free, casein-free and other restricted diets. To get more information about just why these diets are recommended, I contacted the Autism Research Institute (ARI). ARI, one of the first autism organizations in America, is the developer of the Defeat Autism Now (DAN!) protocol. DAN! is a highly controversial biomedical approach to autism treatment. There are many anecdotal stories of children "recovering" from autism as a result of the diets, supplements and other treatments recommended by ARI, and ARI itself has conducted research on its protocols. Mainstream medical professionals, however, feel that aspects of the approach are likely to be ineffective or even potentially dangerous.

The following questions came directly from the About.com Guide to Autism, while the answers were provided by Maureen H. McDonnell, R.N., DAN! Conference Coordinator and former DAN! clinician.

Why Do You Recommend a Gluten-Free/Casein-Free Diet for Children on the Autism Spectrum?

The diet is one of the very first recommendations we make, and consider it to be a cornerstone of the DAN! Approach. The reasons are many: first, many of the children lack the [dpp4] enzyme that allows them to break down the peptides from gluten and casein. As a result, a subset of autistic individuals have these improperly digested proteins which cross the intestinal membrane, travel in the blood, pass through the blood-brain barrier and interfere with neurotransmission. When this happens, Dr. Karl Reichelt, M.D., Ph.D., and other researchers have shown that these opioid-like substances can be responsible for poor attention, odd behavior, a deficit in socialization skills and poor speech. Conversely, when gluten- and casein-based foods are removed, there can be an initial drug-withdrawal phase [when symptoms can worsen], followed by improved behavior, better attention, at times improved speech and an increase in socialization skills.

What Other Related Interventions Do You Recommend?

If a child has gastrointestinal issues, we often go one step further than the gf/cf diet and recommend a specific carbohydrate diet (SCD). The reason here is that in addition to lacking the dpp4 enzyme, many children also are deficient in disaccharides. This research was done by a Harvard professor who is also a pediatric gastroenterologist: Tim Buie, M.D., and his associate Raphael Kusshak, Ph.D. We have found repeatedly that by parents' removing all complex carbohydrates for a period of time, the intestinal inflammation often improves. Subsequently, not only is there an improvement in the consistency and frequency of bowel movements, and a decrease in abdominal bloating and discomfort, but also positive changes in behavior and attention are observed. It has also been shown that the dpp4 enzyme that we need to break down casein and gluten is blocked by mercury. So, in addition to the diet and giving appropriate nutrient supplementation, we also recommend children be properly assessed for heavy metal toxicity like mercury overload. After a child is stabilized on the diet, the gut symptoms diminish and they are being adequately fortified nutritionally (all very important), we often recommend testing and chelation therapy to remove the excessive toxins.

Isn't It Possible That the Positive Effects from the Gluten Free/Casein Free Diet Are Simply the Result of Improved Digestion?

I think your hypothesis that the improvements we see in behavior, speech, etc., are the result of a decrease in GI symptoms, and not the removal of opioid like substances has some merit. However, many researchers like Reichelt, Shattock and others are convinced that the removal of gluten and casein and the subsequent reduction in peptides directly impact those symptoms. It's most likely a combination of both.  
_References:
Email interview with Maureen H. McDonnell, RN DAN! Conference Coordinator and former DAN! clinician. March, 2007.
Christison, G.W., and K. Ivany. 2006. "Elimination diets in autism spectrum disorders: any wheat amidst the chaff?" J Dev Behav Pediatr. 27(2 Suppl):S162-S171.
Cornish, E. 2002. "Gluten and casein free diets in autism: a study of the effects on food choice and nutrition." J Hum.Nutr.Diet. 15(4):261-269.
Elchaar, G.M., et al. 2006. "Efficacy and safety of naltrexone use in pediatric patients with autistic disorder." Ann.Pharmacother. 40(6):1086-1095.
Elder, J., et al. 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.
Erickson, C. et al. 2005. "Gastrointestinal Factors in Autistic Disorder: A Critical Review." Behavioral Science Volume 35, Number 6 / December, 2005
Interview with Dr. Cynthia Molloy, M.D., M.S. Assistant Professor of Pediatrics, Center for Epidemiology and Biostatistics, Cincinnati Children's Hospital Medical Center, March 13, 2007.