"Study Finds Diet Has No Effect on Autism"
That was the headline that sparked my interest in this week's science section in the print version of The New York Times.
Sounds like we have a good old fashioned experiment. Some autistic children assigned to eat a certain diet (gluten-free, dairy-free?) and then compared to those who ate a regular diet. Hopefully with a control group of children without autism.
There's a theory that gastrointestinal issues underlie autism. Correct the tummy trouble via diet, correct the autistic symptoms. And that's just what the lead-in to the study suggests.
So, there I was, all eager to read about an actual experiment.
No such luck. There was no experiment, no random assignment, and thus, no diet effects anywhere in this one. The headline? A complete blunder. The research addressed GI issues more than diet, for starters.
Turns out, Mayo Clinic researchers compared medical records for 100 autistic children and some 200 control children, comparing the incidence of gastrointestinal issues like diarhhea and vomiting between the two groups.
Were GI problems more common among autistic children? No. Although there were no differences in overall frequency of the problems, autistic children were significantly more likely to be picky eaters and suffer bouts of constipation.
So we have a glimpse at the rate of GI problems in kids with and without autism. Is it possible diet effects autistic behavior? Sure, but this study certainly doesn't get at that question. Moreover, the authors suggest the reverse relationship - that autistic symptomotology may lead to picky eating and thus, constipation. The underlying autism, with its attendant sensitivities, creates the tummy troubles.
You could argue that if GI disorders triggered autism we could expect to see more GI disorders among autistic children. And because we didn't, it's unlikely GI issues play a role in the cause of autism. That's fine. Speculative. Possibly even accurate.
But you certainly can't say diet has no effect.
The online version of the piece by Roni Caryn Rabin is slightly different and carries a different though no less troublesome title - "Restrictive Diets May Not Be Appropriate for Children With Autism". Okay, so the study doesn't address whether or not certain diets, or any diets for that matter, are "appropriate" for anybody, let alone autistic kids. Did the editors at least know the print version title "diet has no effect" was inaccurate and try for something more nuanced? Hopefully, but they are still way off mark here. It's remarkable the editors botched the title twice, and perhaps, in a fit of trying for more accuracy. It makes me wonder about the scientific literacy of the people behind the science section. And I do love some of the people, but honestly...
You can read the abstract for free over at the journal Pediatrics.