Testing Wheat- and Dairy-Free Diets for Autism

What happens when children with autism who eat gluten and casein free are secretly exposed to wheat and dairy products?

The first randomized controlled trial of a gluten-free and casein-free diet in autism found that parents reported that their children were significantly better in the diet group than in the control group, but that could just be the placebo effect where “parents” attribute Diet change, also because of the great effort …[so] they will be biased to see “evidence of success” that may not actually be there.

What if you don’t just rely on the parent report? What if you do a blinded study on a gluten and casein free diet like I discuss in my video? Double-blind clinical study on nutrition in autism? In such a study, the parents know what the children are eating, but you don’t just ask the parents how the children are doing; You have investigators objectively judge all children without knowing who belongs to which group – the diet group or the control group. The result? The researchers found “a significant positive group effect on core autistic behavior and related behaviors after 8, 12 and 24 months of intervention on a gluten-free and casein-free diet”. It was one of the largest such studies ever done. It started with 73 children, but about a fifth of the subjects broke out, mostly from the diet group.

“If a family did not feel that their child was making progress on nutrition, they were more likely to drop out, skewing the analysis on those who believed their children were progressing” – for those children for whom the diet seemed to work better. So the remarkable results they’ve had in terms of improved social interaction and fewer ADHD-type symptoms may have come to an end exaggerate the effects of the diet as the children it did not help may have been disproportionately sorted out. In addition, parents were very aware of whether their children were in the diet group or in the control group because they were preparing the meals so they may have changed their own behavior towards their children and this “may have influenced some of those observed”. Patient reactions. “

It’s similar to happens in a famous sugar study in which researchers cheated on mothers and falsely told them their children had just been given a hefty dose of sugar. The mothers not only rated their children as “significantly more hyperactive”, they also unintentionally changed their own behavior. Mothers who mistakenly believed their children had just been given a lot of sugar were observed to have “more control” over their children and to be more critical of them than control mothers. In this way, their expectation of an impact may actually have resulted in an actual impact on their children’s behavior change.

In these open-label autism studies, the parents are tip over Feeding their families in the hope and possibly even in the expectation that their children will be better off. Perhaps the parents even unconsciously treat them differently, so that the children behave differently during the later assessment by the blinded investigators. For this reason, we need double-blind studies in which no one – neither the parents nor the children – knows who is in the diet or control group. Why didn’t the researchers do this type of study? Why didn’t they sneak some gluten or casein into the children’s diet to see if they were feeling worse again? Because it wouldn’t be ethical, just like the researchers in a study that I discussed at length in my previous video Are the Autism Diet Benefits Just a Placebo Effect? had intended. They just couldn’t bring themselves to give the kids gluten or casein because they were so convinced that these proteins could be harmful. However, this decides in advance about the result. That is circular logic. We can’t test if it really works because maybe it really works – but we can’t test it. What?!

Finally, researchers from the University of Florida did broke through the impasse by doing a double-blind study, which is not easy. All meals and snacks had to be provided, so families had no idea whether they were randomly assigned to the gluten-free and casein-free diet group or whether they were actually in the control group, which received the same foods but with gluten and casein. Then, after six weeks, they switched, so the gluten-free and casein-free group started getting wheat and dairy products, and the control group was secretly switched to a gluten-free and casein-free diet.

Before “unblinding,” before the codes were cracked to see who was in which group, parents were asked if they thought their child was on the special diet for the first or second six weeks. Five got it right, two “had no idea” and six were wrong. In other words, it was no better than a chance to flip a coin. In fact, about half thought their kids got better with casein and gluten. So there were “no statistically significant results, although several parents reported improvements in their children”, claiming “marked improvements in child language, decreased hyperactivity, and fewer tantrums” – so much so that some parents decided to keep their children on the gluten-free diet. and casein-free diet, even though the researchers had just told them it didn’t work.

Has something been missed? Some parents had asserts at least a significant improvement. The researchers re-examined the videotapes they made of the children before and after the diet intervention and showed them to blinded examiners. Has the children’s language really got better? Apparently not. The videotapes showed no such improvement, so again the study results did not support the effectiveness of a gluten-free and casein-free diet in ameliorating some of the core symptoms of autism – “at least for a 6-week nutritional intervention. “The non-double-blind studies that showed an effect had children eat gluten-free and casein-free for a year or even two. What does that mean? “Failure to find a statistically significant difference between dietary conditions in the current [double-blind] Study should not necessarily be interpreted to mean that the intervention method does not work in children with autism ”, given“ the relatively shorter duration of the nutritional intervention ”.

The same problem materializes Years later in a 2014 study in Texas. The study design was simple: put everyone on a gluten-free and casein-free diet, then randomly distribute parents to receive weekly bags filled with either gluten-free and casein-free brown rice flour (which complies with the diet) or an identical looking powder mixed with gluten and milk. Until the end, nobody knew who was really gluten-free and casein-free. The result? No significant changes were found in any of the diet groups. Okay, but this study only lasted four weeks and the advocates of the diet propose It can take months for gluten and casein to react.

The problem is, there weren’t any double-blind studies that lasted that long … until recently.

This article discusses the fifth video in a six-part series on the role of gluten and dairy-free diets in the treatment of autism. For the first four installments see:

And have a look at the finale Pros and cons of a gluten-free, casein-free diet for autism.

Stay tuned to all of my autism related videos Here.

You might be curious why I didn’t just go hunting and make a single video on the subject instead of producing this entire series. Well, it’s such a controversial and controversial topic that I wanted to dig into it in depth to provide a comprehensive overview.

If you’ve ever disinterested in a subject I’m talking about, please take a look at the videos on the over 2,000 other topics I’ve already covered it on

In health,

Michael Greger, MD

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