Untangling the Truth about Autism

There are a lot of claims made about autism. What causes it? How common is it? What are the common symptoms? Is there a cure? I can't go through every single claim ever made about autism here, but I'd like to take some of the common ones and sort out myth from fact, and explain why.

• One out of every 110 children is affected by autism in the United States, including one out of every 70 boys. (source)
  This is fact, but a bit misleading. The data that the Autism Speaks report uses is from the CDC's autism report, found here. The study compares the autism rates of 15 different communities, and includes every instance of an autism spectrum disorder. This means that both a very mild case of Asperger's syndrome will be counted as a hit equally to a debilitating case of severe autism, so long as they are diagnosed. Thus, while the numbers are accurate, the statement would be more correct stated as: "One out of every 110 children is diagnosed with an ASD in the United States, including one out of every 70 boys."
• Studies have shown that environmental toxins like mercury and pesticides can trigger autism. (source)
  This one is plausible. There is some evidence that autism prevalence rates are higher where there are higher concentrations of heavy metals and pesticides before birth. However, the results of these studies are still fairly preliminary, as far as I could find from my research, and more studies will have to be done before there is a true consensus on this.
• Sources:
  DeSoto, M. Catherine, 2009. Ockham's Razor and autism: The case for developmental neurotoxins contributing to a disease of neurodevelopment. NeuroToxicology, 30(3):331-337
  Abstract at PubMed
• There has been no study that has directly linked a pure genetics basis for autism. (source)
  False. Plain and simple. There are quite a few studies that link genetics to autism. For instance, this study provides a quite strong correlations between autism and a genetic mutation. This one provides a relatively complete summary of the genetic basis for autism. Even the DeSoto article I linked to above discusses how there is a genetic predisposition to autism, depending on how sensitive an individual is to the toxins. The genetic basis for autism is well-established scientifically.
• Vaccines cause autism (source- note that this is implied throughout the whole "Vaccines" section of the website, but is never stated directly)
  False. This is by far the biggest autism controversy. Because of this, there has been a lot of scientific research. After all, if there was something to the claim, there would be major reason to change the vaccines given. But the consensus has come back with a definitive result: autism is not caused by vaccines. A really good summary of the current evidence can be found in this article. The one study that did show a link between the MMR vaccine and autism was retracted earlier this year, as it was shown to be a fraud. There is no cause for concern that vaccinating children will give them autism. Not vaccinating them is likely to cause them polio, measles, and other potentially deadly diseases, as well as spread those illnesses to other children (source). The risks of not vaccinating far outweigh those of getting the vaccinations.
• Autism is reversible (source)
  While there are treatments available that can help lessen the symptoms of autism, this claim that autism is completely reversible is, as of this point in type, false. As I mentioned here, autism is a disorder, not a disease. A kid doesn't "get sick" and start acting autistic; instead, something is wired differently in their minds, whether due to a genetic mutation or to exposure to toxins during development. As stated on the Autism Speaks website:
  
  

  Most parents would welcome a cure for their child, or a therapy that would alleviate all of the symptoms and challenges that make life difficult for them. Just as your child's challenges can't be summed up in one word, they can't be remedied with one therapy. Each challenge must be addressed with an appropriate therapy. No single therapy works for every child. What works for one child may not work for another. What works for one child for a period of time may stop working. Some therapies are supported by research showing their efficacy, while others are not. The skill, experience and style of the therapist are critical to the effectiveness of the intervention.

This list of claims is far from comprehensive, but these are the five I hear most often, and that cause the most controversy. If you have other questions, feel free to send me an email using the link to your right. Or, better yet, do some research of your own. Talk to a medical doctor, preferably one who specializes in neuroscience; search for relevant studies on PubMed; gather knowledge to be able to sort out fact from fiction. Be aware that not everyone uses science-based medicine, and that even the most well-meaning people can give bad, and potentially dangerous, information. With a bit of skepticism and a little work, though, it is always possible to find good information to make the best choices you can, especially concerning things like autism.

If you want more general information on what autism is, take a look at What is Autism?