Patrick Holford gives the British Dietetic Association the benefit of his high quality research on autism

As Dr Crippen notes, Patrick Holford has taken it upon himself to educate the British Dietetic Association (BDA) on the benefits of dietary interventions for autism. On this blog, Shinga has also analysed Holford’s wisdom on this issue. I’m also going to look over some of Patrick Holford‘s ‘evidence’ base on this.

If you’re going to take it on yourself to lecture a learned body like the BDA, you had better make sure your research stands up to scrutiny. Sadly, the ‘evidence’ that Holford provides for a gluten free casein free (GFCF) diet to treat autism doesn’t stand up to even cursory scrutiny.

Holford’s first piece of autism-specific evidence is a link to Robert Cade’s work. Unlike in other Holford work, the link works this time – I suppose one should give Holford some credit for this. However, he doesn’t get any credit for the quality of this ‘evidence’.

The Robert Cade piece that Holford links to is a short letter on what reportedly happened to some children on the autistic spectrum when they followed a GFCF diet. This isn’t a journal article (or even a letter published in a reputable journal – the letter is reproduced on the paleodiet website). The letter hasn’t been peer-reviewed, and there’s relatively little detail on the methodology. This lack of detail on methodology – along with the lack of peer review – means it’s pretty much impossible to know whether the study referred to was any good. It is hard to see why Holford would want to reference this letter anyway – there have been journal articles on the GFCF diet, so why not reference the academic literature instead of a letter on the paleodiet website?

Holford then cites Jynouchi et al’s paper on inflammatory reactions in people on the autistic spectrum. For Jyonouchi et al, “Immune reactivity to [dietary proteins] may be associated with apparent [dietary protein intolerance] and GI [gastrointestinal] inflammation in ASD children that may be partly associated with aberrant innate immune response against endotoxin, a product of the gut bacteria.” These are interesting ideas and, if people on the autistic spectrum do suffer GI problems then no-one – least of all dietitians – would deny that they should be provided with good quality medical treatment. However, without even starting on the problems with Holford’s conception of IgG reactions, Jyonouchi et al’s paper has nothing to do with Cade and Holford’s apparent belief that GFCF diets can help to reduce “autistic traits” (unless you define GI problems as an ‘autistic trait’).

Holford then cites the Cochrane review of GFCF diets for autism. Holford states that:

A review of wheat and dairy-free diets in relation to reducing autistic traits reported “a significant beneficial treatment effect for the combined gluten- and casein-free diet”.

The Cochrane review is an excellent source – but Holford has chosen an odd way of representing its conclusions.

As part of a commendable attempt to make science accessible to non-experts, the Cochrane review has a nice, clear plain text summary:

Extensive literature searches identified only one randomised control trial of gluten and/or casein free diet as an intervention to improve behaviour, cognitive and social functioning in individuals with autism. The trial was small scale, with only 10 participants in the treatment group and 10 participants in the control group. Results indicate that a combined gluten and casein free diet may reduce some autistic traits. This is an important area of investigation and large scale, good quality randomised control trials are needed.

This gives a very different impression to – and contains far more qualifiers than – the section of the Cochrane review that Holford quotes. Holford chooses to quote from the review’s abstract, instead of the plain text summary. The results section of the abstract states that

The one trial included (n= 20) reported results on four outcomes. Unsurprisingly in such a small scale study, the results for three of these outcomes (cognitive skills, linguistic ability and motor ability) had wide confidence intervals that spanned the line of nil effect. However, the fourth outcome, reduction in autistic traits, reported a significant beneficial treatment effect for the combined gluten and casein free diet.

In other words, there is some, small-scale, evidence of a statistically significant effect on one out of four measured outcomes. It would be easy to get a different impression from Holford’s statement that the Cochrane review finds “a significant beneficial treatment effect for the combined gluten- and casein-free diet”.

The other autism-specific journal article that Holford provides is Green et al’s “Internet survey of treatments used by parents of children with autism“. I’d imagine that – to Holford Watch’s intelligent, sensible readers – many likely problems with this survey will be apparent from the title, but I’ll give a few details here.

As article points out, “the data on most commonly used treatment must be interpreted with caution. Common use may not necessarily indicate preference for the treatment.” And, of course, treatment preference doesn’t necessarily demonstrate efficacy – ineffective and dangerous treatments can sometimes become popular because of, for example, skillful marketing.

Talking about ineffective and dangerous treatments for autism – some of the statistics in Green et al’s article are alarming. They find that 7.4% of children were being chelated and 1.6% were having secretin used on them (down from an alarming 11.3% who had had this drug used on them in the past). It’s odd that Holford chose not to take this opportunity to lecture the BDA on how “valuable [and] naturopathic in concept” chelation therapy is (or its occasional fatalities), or to argue again that the off-label use of the drug secretin is “Worth considering“.

At any rate, I hope that the 20-odd percent of parent who Green et al found had put their kids on a GFCF diet had accessed a better evidence-base than that provided by Holford before they did so. Bear with me – we’re almost at the end of Holford’s attempt to educate the BDA. His final piece of ‘evidence’ is a link – again, not broken, so he gets some brownie points for that – to what looks like a series of e-mails about casein and gluten. Surely Holford doesn’t expect dietitians to base their decisions on how to treat vulnerable kids on a handful of e-mails reproduced online – does he?

To summarise Holford’s evidence on GFCF diets for autism, then, he uses this article to tell the BDA about:

  • One letter describing a small study (not published in a journal, and without enough information on the method for one to assess the quality of the research).
  • An article which suggests that there may be an increased incidence of GI problems and food intolerances in autistic children – which, even if true, does not show that a GFCF could ‘cure’ any children on the autistic spectrum, or that those children without gluten/casein intolerances should follow a GFCF diet.
  • A somewhat misleading quote from the Cochrane review of GFCF diets and autism.
  • An article on an Internet survey on the treatments that parents use on their autistic spectrum kids.
  • A link to what looks like a collection of e-mails, some of which relate to GFCF diets and autism.

I find the idea that anyone would impose dietary restrictions on vulnerable children, basing their treatment decisions on such flimsy evidence, rather worrying. Dietary interventions are certainly not risk-free – or particularly pleasant for the kids involved – so you don’t want to impose them without good reason. As the BDA notes:

Although the perception is that dietary change is much safer than the use of medications,
excluding foods without making sure the diet stays balanced can cause dietary deficiencies,
weight loss and poor growth. The risks increase as more foods are excluded, and children who
are extreme faddy eaters can be at high risk of having an inadequate diet.

There is some interesting evidence that GFCF diets may benefit some people on the autistic spectrum: as the BDA puts it, the evidence on this topic is “inconclusive”; I would therefore support the Cochrane review’s recommendation of further good-quality research. Holford’s analysis of the literature on GFCF diets and autism is, however, sufficiently poor that it is not a useful contribution to the debate. I very much doubt that the BDA will be impressed by Holford’s attempts to enlighten them. I very much hope that healthcare practitioners will not use this ‘evidence’ as a basis for treatment decisions.

Towards the end of his article, Holford quotes from (though, oddly, chooses not to link to) Simon Crompton’s excellent critique of Food is Better Medicine than Drugs. In this piece, the dietitian Catherine Collins argues that “It’s unfair on people to say that dietary treatment can be anything more than an adjunct to medicine when it comes to serious conditions”.

Holford thinks that Collins is being too dismissive of his work. However, having waded through way too much of Holford’s writing on ‘nutritional’ and other ‘alternative’ treatments of autism, I am not convinced that Holford’s approach to autism is even a useful adjunct to more ‘conventional’ support and treatment.

Dietary treatments for conditions such as autism may be valuable when carried out by qualified healthcare practitioners. However, the thought of children on the autistic spectrum being treated by ‘nutritionists’ drawing on the type of ‘research’ analysed above, on Holford Watch ,and elsewhere in the wider Internet frankly fills me with horror.

Holford asks, rhetorically, whether “showing this kind of evidence will shift…thinking about optimum nutrition”. I very much hope that it doesn’t, and that qualified dietitians continue to draw on a much superior research base.

Update: Feb 2009. Chelation is not a risk-free procedure. There are clear indications that popular chelation interventions for children with autism may be contributing to neurological damage. It is long past time for Holford to change his advice and cease to recommend such dubious procedures.



Filed under BDA, catherine collins, Food Is Better Medicine Than Drugs, Jerome Burne, patrick holford

19 responses to “Patrick Holford gives the British Dietetic Association the benefit of his high quality research on autism

  1. Gina

    Is it not a bit sad when you’re reduced to giving credit for a working URL? Isn’t that like giving somebody marks for getting their name right on an exam paper?

    The summary of the truthiness (it debases evidence to label it as such) was accurate but distressing. Who thinks letters and emails are equivalent to papers in indexed, reputable journals?

    Is it time to ask the Hoofnagles if they intend to syndicate their fab. symbols. You know, the ones that flag cherry-picking, crankiness, moving goalposts etc.

    Or – could we adopt a metonym for all of these? Something like a sprig of broccoli eating an apple while clutching a bottle of supplements?

  2. Shinga

    “Dietary exclusion may or may not have beneficial effects in the
    manifestation of autistic symptomatology; it will not prevent
    its development. We need to know more about the links between the immune and GI systems and the brain in autism, to determine whether these are legitimate avenues for novel therapy in selected cases or even for attempted primary prevention in genetically at-risk subgroups.”

    Quoted: Murch, S. Diet, immunity and autistic spectrum disorders (go here to see full text – cough).

    It rather seems that after some salutary experiences with a co-defendant in an up-coming hearing, Prof. Murch is far more circumspect about the issue of GI disorders and ASD.

  3. Jon

    Thanks for the study Shinga – an interesting read.

    Gina said:
    Is it not a bit sad when you’re reduced to giving credit for a working URL? Isn’t that like giving somebody marks for getting their name right on an exam paper?

    One of Holford’s mailing list e-mails – discussing mercury in fish – was listed as coming from the sender ‘Patrickholfrod’. I thought it might be cruel to bring that up, though… As an aside, that seem e-mail also contains some fishy numbers (though these are slightly different figures from the ones that Shinga analyses).

  4. Pingback: Thompson: Holford is “one of Britain’s most influential propagators of potentially dangerous counterknowledge” « Holford Watch: Patrick Holford, nutritionism and bad science

  5. Claire – 17 March, reporting a study in Archives of Disease in Childhood which casts doubt on the ‘leaky gut’ theory and value of GFCF diet.

  6. Pingback: Patrick Holford Promotes Error: Does This Explain His Continuing Support for Opposing MMR and Supporting Andrew Wakefield’s Research? « Holford Watch: Patrick Holford, nutritionism and bad science

  7. Dulcinea

    Where do these self-appointed experts like Patrick Holford get the idea that they know better than people who actually study a subject?

    It takes years to specialise after becoming an RD if you want to concentrate on paediatrics but he seems to think he’s an expert in everything. Children, autism, mental health, diabetes, wireless routers, dentistry, obesity, how other people should conduct research, vitamin C, fish oil, antioxidants. Proper scientists and actual researchers spend decades establishing a reputation in one tiny area – like elucidating and elaborating the metabolic pathways involved in metabolising something like paracetamol.

    It proves that people take you at your own valuation – present yourself as a media expert and you are.

    No wonder the world is in the mess it is in.

  8. Highlander

    Can I suggest that he is a typical self-appointed guru who has come to believe in his own mastery of everything he skims (I won’t say reads because he shows no evidence of giving other authors the courtesy of reading them properly).

  9. Michael & Vanessa

    Reading Patrick Holford on this is like reading a school report from a child who is attempting to impress by using big words that they don’t understand and decorating the text with what look like references that fall apart the moment anyone tries to follow them.

    I can’t believe this man is the CEO of a charity. I wouldn’t donate a red cent to something headed up by someone with this track record. You could never rely on the money being spent wisely.

    Admin edit: sadly, some of the ‘research’ done by this charity was so poor that even the head of their own Scientific Advisory Board had to say that it ‘wasn’t a proper job’ and ‘wasn’t rigorous’.

  10. Highlander

    It’s shocking to think that there are people buying Patrick Holford’s books who think they are getting good advice, based on sound evidence from researchers and doctors but there is nothing there but paranoia, conspiracy fantasies and science that is not always presented in an accurate way – never mind honest.

    • That would be an interesting new category in book shops. Books that are non-fiction where the authors are allowed to make up their own facts.

      It is particularly absurd, however, when authors such as Patrick Holford attempt to build a reputation for scientific support and excellence.

  11. Randall

    So, we’re all waiting for Patrick Holford to issue an update and correction on his recommendations for autism?

    Did you hear the crank-feat of his NZ radio interview? If anything all this will make him more of a true believer and promoter of conspiracy theories and cover-ups.

  12. Randall

    I’ve come up with an idea – next time he is interviewed there should be live blogging and there can be real time responses to his sales pitches and self promotion.

  13. dom fredo

    live blogging is a great engagement tool – the Guardian does it much better than the BBC for the beeb’s own programmes.

    could anyone but a team keep up with the stream of patrick holford’s wishful thinking (can’t call it science)?

  14. Will not Grace

    Patrick Holford is a prime example of someone whose self-esteem and good opinion of himself are derived from his self-esteem and good opinion of himself.

    If he worked in a proper industry he’d have been out on his ear years ago. But he works in a fantasy industry of slim, tanned, glowing with health wannabees so there are always more suckers when the previous ones find out his stuff has no proper foundation.

    It’s bad enough when it is fantasy – but there is no excuse for his evasions when it comes to autism or conditions like that.

  15. Vron J

    You ever get the feeling that Patrick Holford gives helicopter aid? He arrives somewhere in a flurry of noise, stays for a few hours and then makes a swirling exit. He has spent as much time caring full-time for a child with autism as I’ve spent on cruises with people bringing me Mai-Tais.

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