The fact of the matter is, there have been reported individual cases of improvement when altering the dietof someone with autism. However, widespread success rates and the odds of it being successful on a large scale are debatable. The primary premise of an autism diet is to cut out gluten and dairy. The reason for this is based on characteristics of ingredients found in dairy and gluten products that contain properties reported to act like an opiate. This may exacerbate any autistic symptoms that may be present. Cutting out these ingredients may help improve the functionality of someone with autism. This is a fascinating theory and one that holds promise as a possible treatment. However, the facts do not support this as much more than a possible way to fix individual issues on a small scale in some patients.
First, the way the opiate properties are absorbed in autistic patients is via permeable intestines, an ailment more commonly found in autistics. Although it is commonly found in autistics, not everyone who has autism has permeable intestines. In fact only twenty percent do. As far as statistics go, this is much higher than most segments of the population but is by no means a majority of autistic patients. If this is the case, gluten and dairy should have no ill effect and no change in diet will affect the symptoms. The reverse is also true. People around the world eat diets high in dairy and gluten with no ill effects. Some of them are not diagnosed with autism yet do have permeable intestines. No abnormalities are seen in them; therefore, the theory does not seem to be sound as a whole.
So what about the reported incidents of improvement when diet is changed? There is no doubt that this has occurred in some instances. Medical professionals tend to agree the reason for this is an added comfort level on the part of an autistic patient who also has gastrointestinal problems. If you relieve one of the accompanying symptoms of the core disease, the autistic patient may be more comfortable, better able to focus and more amenable to learning and absorbing coping techniques. This will lend to improvement in the overall behavior and ability to function within society. However, no concrete evidence shows that changing diet will affect all autistics in a positive manner in the least.
Because of this, most medical professionals advise a change in diet only for those who have gastrointestinal issues and only on a temporary basis to see if improvement is reached. If there is improvement, continue with the dietary changes of eliminating gluten and dairy from the diet. However, if no change is seen or if the patient has no gastrointestinal problems, it is advisable not to alter the diet in any way. A gluten and dairy free diet is difficult and stressful to sustain and there is no need to go to such extremes if there will be no positive benefits from it.