Blue Collar Scientist

The Bad Astronomer recently brought to my attention Jenny McCarthy’s advocacy of using nutritional supplements and dietary restrictions to treat autism. McCarthy has claimed that diet and nutritional supplements help autistic kids, saying:

“I’ve been speaking to moms across the country who are all shouting out the same thing: ‘This (diet and supplement intake) is working.’”

“It’s so heartbreaking to see the medical community not support something called diet and vitamins. And it pains us, city after city after city. I see this heartbreak on these mom’s faces.”

“Autism isn’t covered by [medical] insurance. If things like diets and supplements are working, then why not support it? These kids are getting better and I will not shut up and will not stop fighting about it.”

This parallels a larger set of claims from the DAN and biomedical folks who claim that certain interventions can cure autism. As is well known, Jenny McCarthy and her fellow-travelers are wrong. Diet and supplements don’t cure autism.

There are lots of people who don’t know this, however, and they hear the kinds of crazy things said by McCarthy, the mercury militia, the biomedical quacks, and sundry other nutjobs, and they wonder about this stuff. Occasionally, they ask, well, why couldn’t diet and nutritional supplements help?

When asked, you could trot out the data and go over the statistics. And that would be a great idea in certain situations, such as if you were addressing a conference, or if you were a physician going over the evidence for an interested parent, or if you were a genuine expert blogger who was going over the data for the rest of us.

For the rest of us, though, we encounter these kinds of questions from our acquaintances - those who know we are rational thinkers, who might be under the impression we are knowledgeable or smart, or at least who know we are likely to have an opinion. What’s the best way to respond to these people?

For my part, I admit that diet restriction and vitamin intake could help. Exercise could help. Avoiding sun exposure could help. Wearing special underwear could help. Appealing to a magic sky-god could help.

But then I change the rules of the discussion and take them on a journey through common sense. Here is what I tell them:

The question is whether it is really likely to help.

Let’s have a look at this question rationally. Autism is a neurological disorder caused by disrupted early brain development. Autistic persons’ brains are characterized by differences in size and mass, excess neurons in certain locations, abnormal synapses and dendritic spines, structural differences in mirror neurons, and a differently-functioning cingulate cortex. Genetic differences have been found in autistic persons. The biological evidence suggests the disorder is a result of genetics and environmental interaction during brain development, which results in the fetus “building” a brain which is anatomically and functionally different from that of a typical human.

Now, there are also people who, due to a combination of genetics and environmental influences, develop abnormal hands, feet, palates, noses, kidneys, pancreases, stomaches and other pieces of anatomy.

Do we find those people’s hands/feet/etc attain normality if they consume a specific diet and take vitamin supplements?

No.

As much as it would be nice if nutrients could rebuild a brain into a standard configuration, there’s no reason to think that they could, if they can’t even rebuild other, simpler organs in a similar way.

Another line of evidence makes it unlikely. We do know about thousands of chemicals that can cause the body to reorganize entire organs and body systems into new configurations. Those chemicals are (a) not nutrients, and (b) deadly. The few that aren’t deadly are highly specialized pharmaceuticals that need careful dosing so as to not cause more harm than good - and most of them work despite their tendency to cause organ development to go haywire, not because of it. Potentially, one or a combination of these chemical compounds, if given in the right dosages over a period of time, might possibly result in re-organizing the brain in such a way to ameliorate autism. The problem is, none of these kinds of chemicals are found in any significant amounts in a normal diet, or in supplements.

So the question becomes: why research nutrients? Why think they might work? There’s already tons of evidence that it would be pointless. In the meantime, there are other avenues of research that we have plenty of reason to think could be helpful. Perhaps neurological drugs could result in more-normal brain functioning. Perhaps some kind of surgical intervention could do the same. Perhaps genetic-environmental interaction research could reveal risk factors, resulting in preventive strategies to bar autistic brain development.

All of these techniques have been proven to be effective in other disorders that have origins similar to autism. Whereas nutrition has been proven ineffective in other disorders that have origins similar to autism.

In a world where resources were unlimited, I’d do formal, double-blind, large-n trials of nutrients. In the real world where resources are limited, however, I’m going to spend my money in the place that prior knowledge shows it is most likely to do good. And similarly, I’d be placing my faith in proven or at least plausible treatments, rather than disproven ones that don’t make any sense in the first place.