Fact or Fiction: MSG-free Diet as Cure for Autism?

The San Francisco Chronicle recently reported on the claims of a Bay-Area biochemist and parent of an autistic child that a MSG-free diet cured her daughter's autism. There is so much to say about this that I hardly know where to begin. 

There is so much information about autism out there, and I find that most of it is written in such a way as to inflame people's fear of autism or to tout snake oil remedies which give people false hope of a cure for autism. This article seems to be a case of the latter. 

The article was very non-specific about the source of the MSG.  It isn't clear whether the claim is about MSG that is used by the food industry to make processed food more flavorful, or about the MSG that is naturally present in many foods. The article hints at the former, as it notes that "MSG is sometimes labeled as flavor or flavoring, soy protein, barley malt, pectin, corn starch or yeast extract." However, according to Wikipedia, MSG is one of the "most abundant naturally-occurring non-essential amino acids." The chemical compound was originally isolated kombu seaweed. 

Does this mean that one wishing to follow this diet should avoid food products labeled with the ingredients enumerated in the article, or does it mean also avoiding foods in which the substance naturally occurs? According to the FDA, MSG occurs naturally in tomatoes and cheeses. Would pizza would be off the menu?

On a different front, the article simply doesn't describe the way in which autism is diagnosed, possible sub-types of autism, and its physical manifestations. 

In my view, one of the main problems in the diagnosis and treatment of autism is that the diagnosis continues to be based on observable behavioral criteria -- does a person display atypical social behavior and language and perseverate over special interests? It is a very superficial way of making a diagnosis. There could be any number of underlying causes of the behaviors. Unfortunately, science does not yet have the tools to diagnose according to any more objective criteria. Autism research is being pursued in many different directions, and brain science is still at an early stage. I do not claim to be an expert on this. But it does seem clear that there are many sub-types of autism that have distinctly different flavors. These different forms of autism are all called autism, currently, although they probably have a wide variety of causes, because they have similar behavioral hallmarks. Many different genes have been identified as having a role in causing autism, but science does not yet know how they interact with each other and with environmental conditions. 

To get back to the MSG article, there is an implication in the article that autism is caused by a chemical dysfunction. This may well be -- in some subtypes of autism. However, autism may also be characterized by atypical brain circuitry. To illustrate this, take a look at this amazing image:

These are "high definition fiber tracking" images of the language system in the brain done by Dr. Walt Schneider of the University of Pittsburgh and shown on the 60 Minutes story "Apps for Autism". The brain on the right is that of a neurotypical person, and the brain on the left belongs to Temple Grandin. You can see that the Temple Grandin's language system has recruited many other areas of the brain. 

I love this image. I have shown it to Singularity's class at school to illustrate that autism can be caused by brain differences. Temple Grandin's brain is different. It has found different pathways to accomplish the same things as the neurotypical brain. Difference is value-neutral. It is neither better nor worse. 

But I digress. 

There is simply no way that switching to a MSG-free diet (again, whatever that is) would change Temple Grandin's brain circuitry. For her form of autism, at least, the MSG-free diet is not a cure. 

I don't know if a MSG-free diet would help to prevent the development of autistic brain circuitry, and neither does the biochemist-mom or the author of the article. 

The article's author did consult some autism experts who were skeptical, from a scientific point of view, as there is no scientifically-tested evidence to back the MSG-free diet. However, the article ended with the biochemist-mom's assertion that this diet has been effective in 74 of 75 cases in which she has tried it. This seems like an unsubstantiated claim, and the article's author does not ask to see the clinical evidence. 

If I sent this reporter an email claiming to have cured my son's autism by eliminating unfiltered water from his diet, could I get an article published?

The article doesn't even end by saying that further research is needed. It just gives the biochemist-mom the last word. Is the newspaper not aware of reader behavior (of which I am often guilty) of only looking at the beginning and end of an article???

And so, here we have another article appearing in the mainstream media that may send desperate families on another wild goose chase for a cure for their children's autism, based on hearsay rather than scientific evidence. To say the least, I would like to see a higher standard for science and health reporting.