Celiac.com 09/13/2008 - In the last two decades, research has begun to focus on gluten’s effects on the brain, including associations with Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD).  Celiac disease itself occurs no more frequently in children with ASD than in neurologically normal children, but it appears there are other reasons to consider excluding gluten from the diet. “Mal-digestion of dietary proteins, particularly casein (from cow’s milk) and gluten-containing foods, produces small peptides (amino acid sequences) that may function as opioids”.   This is what is known as “The Peptide Theory”, also called “The Opioid Excess Theory”.  What this means is that incomplete digestion of specific foods allows the remaining small protein fragments, called peptides, to pass through the gut wall into the bloodstream.   Peptides are tiny, but children affected by dietary peptides often have what is termed a “leaky gut”, or a gut that is in some way damaged and unable to fully perform its protective function. In children (and adults) with ASD, gluten breaks down into a peptide called gliado-morphin, and casein breaks down into a peptide called caso-morphin. Eventually these peptides are thought to bind to opioid receptors in the brain, where they are perceived by the body as morphine-like substances.  It is this morphine-like or narcotic-like effect that causes many of the typical behaviors associated with ASD.  These behaviors can include sensory problems, lack of eye contact, self-stimulation, and altered pain threshold, among others.  Repeated exposure to gluten and casein causes a condition similar to opiate addiction - children with this condition often crave the very thing that is causing their problems; consequently, sudden, complete elimination of gluten and casein from the diet can cause withdrawal symptoms.  The discovery of caso-morphin and gliado-morphin in the urine of autism patients may be strong supporting evidence for the peptide theory.

Many parents and practitioners believe in also excluding “excitotoxins” such as dyes, food-additives, MSG, and sweeteners containing aspartame from a child’s diet (Excito-toxins are also suspected to play a role in Attention Deficit Disorder (ADD) and ADHD). Complete allergy testing, as well as testing for Candida (systemic fungal overload) is also recommended.  A good time to do this is after your child has improved somewhat and is stabilized on a gluten-and-casein-free diet.  You will know when your child is ready to move on to the next level.  Careful treatment by a clinician skilled in working with special-needs children is essential, and certain types of body work such as IMT (Integrated Manual Therapy) can be important in tackling these challenges.  Patience is important – it may take only a few days for milk-derived peptides to leave the body, but gluten-derived peptides can persist for several more months.  Discuss keeping a food diary, and appropriate timelines for an individual child’s response to a special diet, with your practitioner.

For those skeptical of altering a child’s diet to effect positive behavioral and neurological changes, there are some small clinical studies (and more needed) and thousands of anecdotal reports from grateful parents whose children have demonstrated spectacular and lasting changes from a gluten and-casein-free diet.  That is not to say that the diet is completely “curative”, or that an unrestricted diet that includes gluten and casein “causes”