Glutens are proteins found in the Plant Kingdom Subclass of Monocotyledonae (monocots.) These plants are members of the grass family of wheat, oats, barley, rye and triticale, and their derivatives. Derivatives include: malt, grain starches, hydrolyzed vegetable/plant proteins, textured vegetable proteins, grain vinegars, soy sauce, grain alcohol, flavorings and the binders and fillers found in vitamins and medications. Casein is a phosphoprotein of milk, which has a molecular structure that is extremely similar to that of gluten.

The following article was written by members of the Autism Research Unit of the University of Sunderland (Great Britain) and is reprinted with permission. [Text in brackets are my additions.]

"The Use of Gluten and Casein Free Diets with People with Autism"

These notes should be taken as observations. They do not constitute a recommendation or endorsement of a dietary method to alleviate the symptoms of autism. Any decision to undertake such a method must lie solely with the person with autism or with those having responsibility for their care.

Background In the early 1980's a number of researchers, including Herman and Panksepp, noted the similarities between the behavioural effects of animals on opioids, such as morphine, and the symptoms of autism. In a very speculative paper, Panksepp proposed a mechanism whereby people with autism may have elevated levels of opioids which occur naturally in the CNS (= brain) of humans. The best known of these naturally occurring opioid compounds is beta-endorphin (= endogenous morphine) and certainly there is a degree of correlation between the known effects of this compound and the symptoms of autism.

Just after this, Gillberg produced evidence of elevated levels of "endorphin like substances" in the cerebro-spinal fluid of some people with autism. In particular, elevated levels appeared in those children who appeared to feel pain less than the normal population and who exhibited self-injurious behavior. At about the same time, Reichelt produced evidence of abnormal peptides in the urine of people with autism. We ourselves, like a number of other groups, attempted to replicate his findings. Although his technique was comparatively simple there were technical difficulties and these attempts were, initially unsuccessful. Later on we switched to a more sophisticated technique and have been able to confirm Reichelt's findings. In the urine of about 50% of people with autism there appear to be elevated levels of substances with properties similar to those expected from opioid peptides. [emphasis added]

The quantities of these compounds, as found in the urine, are much too large to be of CNS origin. The quantities are such that they can only have been derived from the incomplete breakdown of certain foods. Proteins consist of long chains of units known as amino acids. Normal proteins are digested by enzymes in the intestines and are broken down into these units. However, if for some reason, this digestion is incomplete, short chains of these amino acids (known as peptides) will result. It is proposed that these peptides may be biologically active and could result in the symptoms which we see in autism. The majority of these peptides will be dumped in the urine, which is where Reichelt and we are finding them. A small proportion will cross into the brain and interfere with transmission in such a way that normal activity is altered or disrupted. It may be that these compounds, themselves, have a direct effect upon transmission or that they will attach themselves to the enzymes which would break down our own naturally occurring enzymes. The consequences would be the same in either case.
It is well known that casein (from human or cow milk) will break down in the stomach to produce a peptide known as casomorphine, which, as the name implies, will have opioid activities. Similar effects are noted with gluten from wheat and some other cereals [notably oats, barley and rye] in which the compounds formed are gluteomorphins [or gliadinomorphins.]

If this opioid excess hypothesis is correct, there are a number of strategies which can be adopted. Firstly the anti-opioid drug "naltrexone" could be considered and promising results have been reported. [Note: a recent study of 41 children conducted by Magda Campbell, did not produce positive results with low doses of naltrexone. It is possible that doses were too low, but for now effectiveness of this medical intervention must be questioned.] Alternatively, a diet which excludes casein (milk and dairy products) or gluten (wheat and other grain products) could be considered. It may be possible to determine, from the pattern of the urinary peptides, whether casein or wheat [gluten] or both should be avoided, but such conclusions may be premature at this stage. It has been observed that those children whose autism appears at or around the time of birth may have a problem with casein whereas those whose autism becomes apparent at about two years of age, when a wheat based diet is more likely to be adopted, have particular difficulties with gluten. Some children may have difficulty with both.

Norwegian colleagues of Reichelt have published data which support the effectiveness of such dietary programmes but these studies cannot be considered as conclusive. There have been no other real attempts to demonstrate the effectiveness of such diets on a scientific basis. Numerous people have experimented on an individual basis and have reported successful responses but such evidence cannot be considered as, in any way conclusive. In Rimland's studies of parental reports, however, the results appear to be very much superior to those obtained with any drug based theory.

Practical Aspects
The theoretical processes described here are toxicological in nature rather than allergic. The results are akin to poisoning rather than an extreme sensitivity such as occurs in coeliac disease or sensitivity to certain food colourings [see discussion of celiac disease below for another perspective on this topic.] Removal of gluten and/or casein containing products requires the active participation of all those concerned with the child's well-being. Tests have often been ruined by a well meaning relative who ignores parental instruction, or by schools or therapists who feel that the proposals are rubbish. Carers must satisfy themselves that the diet is being adhered to before any evaluation is possible. Gluten and Casein free products, together with advice on their use, are available from Pharmacies [in this country health food stores will be the best source.] Nutritionists and dietitians would also be able to advise.

Initially the reported effects may be negative, upset stomach, anxiety, clinginess and slight ill-temper. Experience would suggest that these are good signs and precursors of a positive response. Reichelt recommends a trial period of three months. If it has not worked within that time it is unlikely to do so. [Note: in electronic mail to me, Reichelt suggests a period of one year is necessary.] Experience also suggests that the results are more easily demonstrated in younger children. The effects in fully grown individuals appears less impressive. Given that there appear to be a number of possible causes of autism it is not unexpected that no unitary solution will be found for all cases.

Conclusions
Although the hypotheses may appear "off the wall" in many respects, there are a number of pieces of evidence which support them. The ideas are compatible with virtually all the accepted biological data on autism and are worthy of consideration.
The dietary method must still be considered as experimental and no positive results can be promised or are claimed. The use of diet may well be far less harmful than other medical interventions or therapeutic regimes. We would be pleased to receive any feedback of a positive or negative nature from anyone utilising such dietary modification in the amelioration of autism.

- Lisa Lewis