Why special diets and which diet?

Beth Hodges, MD

            One of the most frequently asked questions about autism spectrum disorders (ASD) is, “Would changing my child’s diet make a difference?”  The definitive answer is…most likely, yes.  Studies have shown conflicting results, but the bottom line is that many children definitely seem to have improvement with removal of certain substances from their system.  Two potential culprits showing the most promise of improvement from removal are casein and gluten.  Casein is a by-product of milk and gluten is found in wheat products.  Frankly, many experts in the field cannot agree as to the significance of these substances in the autistic child, but the fact is that many children with autism experience an unusually large proportion of diarrhea or constipation and digestive upsets.  Those types of symptoms are very prominent in both gluten and casein allergies, which does lend credence to the theory.  Another often successful diet is the SCD diet (special carbohydrate diet.)  There are several other less commonly used diets, such as the phenol-restricted diet and the Feingold diet that have also shown promise.  

          Children need a variety of nutrients in their diets to grow, but if done correctly, these substances can be removed safely without affecting normal physiology.  Isn’t it worth a try?  If an autistic child shows evidence of an inflamed bowel, such as with chronic diarrhea, stomach upsets, severe constipation, unusually large soft stools, these diets should definitely be tried.

              Once a decision is made to try these diets, the next step is implementation.  The current recommendation is to remove one substance at a time, parents’ preference.  Do not try to remove the other substances for at least a few weeks or months; autistic children do not adjust well to change and a sudden radical shift in diet will be anxiety-provoking.  It also can take a while for the effects of substances to clear.   Casein by-products clear the body faster than gluten, so many parents prefer to try removing dairy first. Casein can clear the body in about thirty days, whereas gluten-free takes about four months to take effect. 

             With the casein-free diet, once milk and dairy (ice cream, yogurt, cheese, etc) have been removed, other forms of protein intake need to be increased to support normal growth and development.   Almond or rice milk can be substituted safely. Soy may or may not be tolerated, so wait awhile to try adding that substance.   Additional calcium and Vitamin D need to be added to the diet as well.  Beans, eggs, meat, fish, and poultry are all good sources of protein.

            Gluten is a little trickier to remove, as that includes wheat, barley, and oat products.  Luckily, awareness of celiac disease, or gluten allergy, is on the rise and many grocers now carry whole lines of substitute products.  Potato, corn, rice, quinoa, or bean products can be substituted.  It does involve some shopping around as well as trial and error, as some gluten free products taste like, well, gluten free. 

             The Special Carbohydrate Diet essentially involves avoiding simple sugars.  The theory is that an overgrowth of yeast can cause both the bowel inflammation and dramatically worsen the symptoms of ASD.  Clinicians who have placed these children on antifungal medications for six months at fairly high doses have seen tremendous improvement after the second month.  It has been noted that regression of symptoms sometimes occurs two years after starting that diet, the reason unknown thus far.  

          The Feingold Diet is based on the principle that certain fruits and other foods contain a chemical that can be converted in the body to salicylate (aspirin) and that some children have a sensitivity to that chemical that can affect behavior.  

            Children with ASD tested for food allergies often show a much higher rate of sensitivities than the general population.  Those sensitivities tend to decrease with time in children who are experiencing improvement, lending credence to the allergen theory. 

           Anyone talking about special diets in ASD would be remiss not to mention the potential benefit of fish oil (omega-3) supplements.  Many children with ASD or pervasive developmental delay (a precursor to a diagnosis of autism in a very young toddler) have shown benefit from the addition of such a supplement.  These can be found now in both liquid and chewable gel candy form.  It does make a certain amount of sense, as civilizations have often touted fish as “brain food” and fish oil supplements are thought to retard the development of Alzheimers.  Perhaps one of the reasons previous generations saw less autism is because mothers were always forcing cod liver oil down children’s throats. 

             One final thought on diet and ASD.  It is best to avoid anything that can cause agitation or restlessness, such a simple sugars, caffeine, and cold medications.  Anything that upsets the normal brain patterns of an autistic child is deeply unsettling to them and can make for a bad day for everyone.  This means no Kool-Aid, punch with sugar, sodas, fruit juices, candy, sweets, etc. 

             Parents of children with ASD often feel helpless and frustrated by their inability to “fix” their children. Implementing and trying the recommended diets is a way to be very proactive.  Every child deserves a trial of the diets.  Be aware, however, that to see true results, the compliance has to be very strict.  One tiny deviation has been known to result in regression of behavior for even up to several days.