Holford Watch: Patrick Holford, nutritionism and bad science

In an Independent article, Holford appears to confuse wheat allergy and gluten intolerance. On March 30, his 100% Health e-mail newsletter asked “Could gluten be undermining your health?” However he seems, again, to have conflated allergy and intolerance.

Holford begins the e-mail by saying that “Gluten allergy - or coeliac disease - used to be considered a rare condition, but new research suggests that 1 in 100 may be affected”.

The Food Standards Agency (FSA) has a nice clear account of the difference between food allergy and intolerance:

Food allergy and food intolerance are both types of food sensitivity. When someone has a food allergy, their immune system reacts to a particular food as if it isn’t safe. If someone has a severe food allergy, this can cause a life-threatening reaction.

Holford usually claims some significance (not supported by expert opinion) for IgG levels as diagnostic of food intolerance; however, one thing on which most people agree is that this sort of food intolerance doesn’t involve the IgE immune system and is generally not life-threatening. But if someone eats a food they are intolerant to, this could make them feel ill or affect their long-term health.

Coeliac disease can be wretchedly debilitating - the symptoms from this can be horrible. However, unlike an IgE-mediated allergic reaction, diagnosed and managed coeliac disease is unlikely to cause a sudden-onset of life-threatening problems. Coeliac Disease provokes a non-IgE mediated reaction brought about in genetically susceptible individuals by exposure to the gluten in wheat and other cereal grains; it functions through a different mechanism to an IgE wheat allergy. It’s therefore important to distinguish between the usual sort of wheat allergy and intolerance that Holford usually conflates and Coeliac Disease - but Holford often fails to do this.

The FSA is right to say that “[i]f you think you have a food allergy or intolerance, then it’s important to get a proper diagnosis.” However, in the 100% Health e-mail Holford suggests hometesting for IgAtTG - by a wonderful coincidence, Holford’s Health Products for Life sells such tests.

Looking on pubmed, IgAtTG was formerly recommended for checking that coeliac patients have been sticking to their gluten-free diet. More recently, Biocard has been promoted as a form of rapid-testing for Coeliac Disease; however, although these tests have been validated, and are comparatively easy for an expert to interpret, it is not necessarily straightforward for the general consumer (see also, Update 2). It is possible for a test to have very high specificity and sensitivity when used by appropriately trained and experienced personnel but to have very different accuracy when used by the general consumer who is (presumably) seeing and using the test for the first time.

However, Holford markets this test as reliable for home use and tacks between discussions of wheat allergy, intolerance and Coeliac Disease, conflating IgG and IgE mechanisms and sometimes equating this conditions. It is vitally important to distinguish these because they have very different implications for quality of life; [update, April] as pointed out in our comments, people with Coeliac Disease qualify for financial support and prescriptions to defray the costs of what would otherwise be very expensive diet. They also qualify for expert guidance from dietitians.

The only article Holford mentions* as support for his marketing is an article I haven’t been able to find in pubmed, or in the referenced journal’s table of contents.

Holford also notes that testing for IgAtTG will ‘diagnose’ celiac disease in a surprising number of people:

[t]he old view was that about 1 in 5,000 people had coeliac disease, the genetically transferred digestive and malnutrition disorder caused by an extreme allergy to gluten. However, new research shows that gluten allergy affects possibly as many as 1 in 100 normal, symptom-free people, often showing no digestive symptoms at all

This is an on-going debate among researchers who have dedicated their work to this topic. If a new, relatively unvalidated as a direct-to-consumer test ‘diagnoses’ a disease in apparently healthy people, the first ‘obvious’ question is whether the test is generating false positives. A second obvious question is - if the ‘disease’ isn’t causing any ill health - whether there’s any reason to modify one’s diet (there may be) and if there are any consequences to transforming someone into a potentially ill person. As explained on the wonderful BreathSpa blog, even if a reliable test shows “sensitisation” to a substance, if this is not causing any problems then this sensitisation may “not [be] clinical disease”, and it might be inappropriate to treat it as such. The consultant allergist Dr Scadding goes on to argue that:

you can not have self-testing kits: they’re going to lead to mis-diagnosis, mis-allergen avoidance. You need both the test and a detailed history taken by somebody who has some experience of allergy history taking and interpretation of tests.

To summarise, then, Holford makes the dangerous mistake of conflating wheat allergy and gluten intolerance. He also advocates - and sells - what he calls “gluten allergy” testing kits. Holford is promoting these these kits as diagnostic of Coedliac disease and what he styles as gluten intolerance; however, looking at the peer-reviewed medical literature, I can’t find convincing evidence that they actually work for intolerance in the sense that Holford typically uses this term. The final nail in this proverbial coffin is that - even if these tests did work (and they are part of the portfolio for managing Coeliac Disease) - it’s unlikely that home testing would be appropriate. For Coeliac Disease, you need a qualified gastroenterologist or similar to take a case history, and to interpret whether or not the presence of IgAtTG antibodies in the blood does show the presence of a clinical condition (which requires treatment with gluten-free diet etc.). Following such tests, you may need to confirm the diagnosis with an endoscopy and/or biopsy.

Neither Coeliac disease, nor wheat allergy, are trivial matters. They need to be diagnosed and treated properly, not using an home test that may be inappropriate for direct-to-consumer use - sold by a nutritional ‘expert’ who fails even to distinguish wheat allergies and intolerances or Coeliac Disease.

Update 4 Jan 2008: Coeliac UK expresses caution about these home tests.

While we welcome a new tool that could help to get more people diagnosed we would stress that blood tests for coeliac disease are not 100% accurate and there are individuals who may have false negative results - even if they have not changed their diet. The self-testing kits should not replace a medical diagnosis and we recommend that if anyone has symptoms of coeliac disease they should go to their GP. [Coeliac UK goes into more detail (pdf).]

Update 2 16 Jan: There may be a role for such rapid test facilities for Coeliac Disease when used by a GP or Practice Nurse (Medscape; free on registration). However, a recent study of population screening for Coeliac Disease among 6-year-olds is a useful illustration that the specificity and sensitivity of a test may change, depending on who is interpreting the results. E.g., in this study District Nurses (the majority of whom had received some basic level of training) performed the rapid testing with the same test that Holford promotes, and yielded a disappointing 78.1% sensitivity but excellent specificity of 100%.

The rapid test seemed to be as accurate as laboratory testing and had a high positive predictive value and specificity. Some training is needed, however, to enable faint test lines to be recognised when circulating antibody concentrations are low. As with all visual tests, observer variability can affect the results, so the diagnosis should always be verified by histology.

It is for these reasons that Holford Watch questions whether it is truly ‘empowering’ for consumers to be persuaded to pay for a test that they may not be able to interpret correctly and would need further validation from a GP.

There is an interesting discussion to be had about the cost-benefit to the individual and society of mass-screening for Coeliac Disease. There is undoubtedly a need for more education and awareness of Coeliac Disease; however, this discussion is hampered when self-styled experts confuse the matter for the general public by conflating Coeliac Disease with IgE food allergies or so-called IgG food allergy/intolerance.

Notes

*Gerarduzzi T et al. Celiac disease in USA among risk groups and general population in USA. Journal of Pediatric Gastroenterology and Nutrition. Vol 31 (suppl) 2000: pp S29, Abst 104. [Having searched Jnl of Ped Gastro and Nutr, this paper doesn't seem to exist as per this reference. It appears in Google Scholar as a citation only which might indicate an error.]

Issues around HIV/AIDS treatment and vitamins are currently in the news due to Matthias Rath’s recent rally in London. That makes it a good time to come back to some of Holford’s statements regarding on the advantages of vitamin C over the anti-retroviral drug AZT.

Holford - responding to media controversy during a tour of South Africa - acknowledges claims that he has “been saying that Vitamin C is more effective in treating AIDS than the anti-retroviral drug AZT.” Holford argues that it “is not true” that he said this. Unfortunately, Holford appears to have a novel grasp of the meaning of words like ‘more’.

Holford had originally stated that “AZT, the first prescribable anti-HIV drug, is potentially harmful and proving less effective than vitamin C“. I don’t mean to patronise readers here, but I’ll quickly lay out why Holford does in fact state that vitamin C is proving more effective than AZT.

Lets say you have two glasses of water. If glass one has less water than glass two, glass two has more water than glass one. Likewise, if AZT is less effective than vitamin C, vitamin C is more effective than AZT. Therefore, by claiming that AZT is less effective than vitamin C, Holford has claimed that vitamin C is more effective than AZT.

Given the numerous unneccesary deaths currently taking place in South Africa (and elsewhere) - in part because certain groups and individuals are pushing and selling vitamin pills as better than anti-retroviral therapy - this is a very stupid area in which to make inaccurate statements. Bearing this in mind - and given that Holford was going on a tour of South Africa - he could at least have made his position and convictions clear.

If Holford realises that anti-retroviral drugs are, currently, the best available treatment for HIV/AIDS, then he should offer a full apology for his misleading statement - instead of squirming around and trying to imply he never said something that daft in the first place. On the other hand, if Holford believes that vitamin supplements should be used to replace proven anti-retroviral drugs - a move which would see thousands more Africans dying unneccesarily - then he could at least have the courage of his convictions, instead of trying to hide behind his wordplay.

Yesterday’s Independent carried an article on ‘What Not To Eat’. A large part of the article was based on Holford’s recommendations, and there are a number of problems with the article. I’ll list a few of them below, but the first thing to note is that readers might want to e-mail a letter to the Independent editor - to let them know what you think of the article.

I don’t have time to list all the problems with the article here (it’s sunny outside again, and I don’t want to be spending too long blogging). Here’s a few that stand out, though:
- The article describes Holford as a ‘nutritionist’, but doesn’t make clear that this isn’t a protected title in the UK: anyone can call themselves a nutritionist. Holford is able to call himself a nutritionist despite lacking any accredited university degrees in this area (his only accredited degree is a BSc in Experimental Psychology).
It’s easy to become a ‘qualified nutritionist’, too. For one day only, I’m offering a DipHWNut: buy me a pint, and I’ll confer on you, too, this super-relevant qualification that lets you call yourself a qualified nutritionist. Fame and fortune awaits!
- Holford claims to be “a vegan who eats eggs and fish”. That is what us non-experts call ‘not a vegan’: a vegan is someone who “does not consume or use animal products“. I’m not saying that people shouldn’t eat animal products - I do this myself - but don’t call yourself a vegan if you do.
- Holford appears to make the basic error of confusing food allergies and intolerances. He claims that wheat is one of “the two most common food allergens“; however, the Food Standards Agency describes wheat allergy as “not very common in the UK“. Wheat intolerance is more common, but is quite different from an allergy. It’s very important to distinguish between the two, especially if practicing as a nutritionist.
Anyway, the fact that gluten intolerance is relatively common does not mean that those of us who are not allergic to or intolerant of wheat should stop enjoying wheat products. Good bread is a real pleasure, and a nice British tradition - it’d be tragic to lose this based on dodgy nutritional advice.
- Holford argues that sunflower oil is one of the best types of fat for vegetarians to eat, but this oil is high in omega 6 fats. It seems that eating a relatively high ratio of omega 3 fats to omega 6 fats is beneficial (pdf). Foods rich in omega 6 fats - such as sunflower oil - should therefore be enjoyed in moderation, and not be used as a major part of one’s fat intake*.

Some people may need specialised nutritional advice - they’d do well to see someone who knows what they’re talking about (e.g. a qualified dietician). After all, cutting out large numbers of foods from your diet (e.g. Holford appears to advise avoiding wheat and dairy) without good reason can be unhealthy.

Look - for most people, good nutrition is largely commonsense. As Ben Goldacre likes to say, ‘eat your greens‘. We don’t need self-proclaimed nutritional experts to tell us ‘what not to eat’. We just need our own common sense to tell us what healthy foods we should be enjoying, and which foods are best enjoyed only in moderation.

JonHW (DipHWNUT)

*research in this area is ongoing, and in my understanding is not yet conclusive. However, I still would not view eating lots of omega 6 fats as good nutritional advice.

Right, more analysis of the ION foundation science degree info brochure, as promised. In the first year, students “will study ION’s method of analysing a client’s health status via a comprehensive health questionnaire” (p. 7). One would really hope that the techniques they learn are better than those in this questionnaire. Maybe the ION’s teaching of questionnaires is along the lines of - do as we say, not as we do.

In year 2, students learn how “Tests, when used appropriately and interpreted correctly alongside other client information, are a valuable diagnostic tool for nutritional
therapists.” (p.7) Yes, (some) tests can be valuable, when correctly interpreted. However, organisations linked to ION have recommended that I get a somewhat peculiar range of tests based on an online questionnaire, and based on the Brain Bio Centre’s incorrect belief that dyspraxia is associated with low intelligence. Aside from recommending, um, unusual tests, Holford also supports the use of IgG tests to diagnose food intolerances - which they cannot do reliably.

Students therefore need to hope that - while some people and institutions linked to the ION do not always design questionnaires well and sometimes recommend unnecessary and/or ineffective tests - the ION will be able to educate them effectively on these subjects. Would you be confident that a Foundation Degree in science from the ION really does offer solid foundations?

Anyway, that’s still only got me to p.7 of a 25 page course brochure. It’s sunny outside, so that’s enough blogging for today. At this rate, I might get through the information brochure this month, if I’m lucky. Sorry if this is boring people - sure I’ll find other things to write about, too.

Looking into the ION ‘foundation science degree’, I was reading through their info brochure. The first thing that hit me were the adverts - not what you’d usually expect in an academic brochure. For example, on the front of the brochure there’s a big, colourful ad for Revital - whose website currently is currently advertising a training event in Psychic Surgery and Spiritual Healing. Well, it’s important that science students learn these skills, I think. And, if they can demonstrate them in controlled conditions, there’s an easy million dollars available to them - bye bye student loan! Admittedly, all who’ve tried this under controlled conditions have failed - but a trained ION scientist could always be the first!

Anyway, struggling to look past the (very bright) ads in the brochure, it’s worth looking at the actual text. David Nicolson (ION Executive Director) notes that studying nutrition is topical because “[m]emories of…foot and mouth
are still fresh in most of our minds” (p. 3). I’m not entirely sure of the relevance of foot and mouth for human nutrition: this infects animals with cloven hooves (and a couple of other species - hedgehogs and elephants, for example). So, unless a nutritionist’s client has cloven hooves, or is an elephant (I’ll omit the obvious fat joke here), foot and mouth disease probably isn’t a major concern*.

Of course, when choosing where to study the history of the institution is important. The info brochure claims that “[t]he Institute was founded in 1984 by Patrick Holford [who developed an] innovative application of principles that are now universally recognised as the benchmark for Optimum Nutrition.” (p. 4) Universality is an easy thing to falsify - I don’t recognise Holford’s principles as the benchmark for ‘optimum nutrition’, so they’re not universally recognised. Of course, there’s no particular reason to take notice of what I say - so one should also look at whether more prominent people have challenged Holford. They have - for example, the prominent dietician Catherine Collins has been critical of Holford’s ‘principles’.

So, that’s one false claim of universal recognition in the brochure, one unusual advert, and one somewhat dubious reference to Foot and Mouth disease - and we’re only on p4 (of 25!) The problem with ION and Holford producing so much problematic material is that there’s no way one blog can get through it all! I’m only at p4 of the ION course brochure, and I’ve already spent too long on it - I need to get on with some work, and will get through more of the brochure another day.

*Foot and Mouth disease can, rarely, be caught by humans - but this is through contact with infected animals, so will not be a nutritional problem (except, perhaps, for those who raise their own meat). Even in these cases, humans rarely catch this disease - between 1921 and 69 there were about 40 confirmed cases in the world.

My first degree was a BA - and, by the end of it, I’d got a bit fed up with all the ‘what do you say to an arts graduate? Coke and large fries with that’ jokes from science students. So, it’s good to see (pseudo)science degrees coming in for some criticism too.

UCL chemistry prof. David Colquhoun has recently been making the news with his criticisms of BSc degrees in homeopathy - arguing, not unreasonably, that a BSc in pseudoscience will be unscientific. Colquhoun’s also written a bit about the Institute for Optimum Nutrition’s (ION) links to Bedfordshire University - with all the publicity for degrees in homeopathic pseudoscience, I think now would be a good time to look again at this ‘degree’.

The ION offers a DipION, which Bedfordshire accredits as a foundation science degree. This foundation degree also lets students get a BSc in Nutritional Sciences with only 1 year of additional work. As you might expect, I’ve got a few problems with this.

The ION looks rather strange for an academic institution. Holford - its founder and director - has really struggled to engage in and with scientific debate. I’ve listed a few examples of this on the blog - with lots more to come…limited more by the time available to write about the than by limited amounts of material - but I think Holford’s response to the JAMA meta-analysis of anti-oxidant vitamins will make a good case study. As I’ve shown, Holford gets almost every aspect of his response wrong - this is not the type of response the one would expect from someone with a good understanding of the science around nutrition, or even an intelligent layperson. Chairs/directors of university departments are generally well-respected academics, with an excellent knowledge of their subject; Holford’s difficulties in reading a (pretty straightforward) JAMA article might lead one to question how well he can lead the ION’s academic programmes.

There are also issues around the accountability of ION staff. Academics (and even poor students like me, who do part-time work helping out with university teaching) are bound by university disciplinary procedures, equal opportunities policies etc. Some of Holford’s behaviour - not declaring his competing interests in his BMJ Rapid Response, implying that his BMJ Rapid Response is a proper publication, incorrectly associating dyslexia and dyspraxia with low intelligence, among other things - would be problematic for those working in an accredited university. Unfortunately, I can’t seem to find a complaints/disciplinary procedure, equal opportunities policy, etc. for the ION - and I certainly can’t find anything like the type of open and accountable procedures that you’d expect from an accredited university.

Of course, the concern isn’t just with ION’s management. For a science degree, the entry requirements are, um, interesting - for example, those with no knowledge of chemistry can get around this requirement by taking a course which covers 3 weekends, and is followed by a 2hr exam. Now, I’m sure these are 3 very challenging weekends, but it doesn’t really compare to the requirements for a ‘normal’ science degree (I should know - I was considering physics at university, but the fact I only had Physics and Computing at A-level, and not Maths, pretty much ruled that out).

Of course, quality research comes from some odd places - so it’s worth a look at how the ION stacks up as a research institution. Well, academics who’ve struggled to stop undergrad students from referencing wikipedia in their coursework will be delighted to see that this is now acceptable in high quality academic publications such as the ION journal.

As well as this type of trend-setting, ION hosts the Brain Bio Institute clinic which offers a diagnostic questionnaire - analysed here - which does not demonstrate even a (good) undergraduate-level understanding of the issues. Aside from typos and questions that don’t make sense, this questionnaire will also diagnose you with a whole range of likely health problems for no apparent reason, and give potentially dangerous false negatives (e.g. diagnosing a 0% chance that allergy is causing you problems based on an online survey!) As an undergraduate project, this could get students into real trouble - both due to the poor quality of the questionnaire, and the ethical issues around the potentially harmful advice the questionnaire gives out.

Anyway, I haven’t got time to go through more of the ION’s publicity materials, research etc. here - I’ve got to get on with some research of my own. I’ll get back to this another day - but, given what we now know about the high quality (pseudo)science degrees available in homeopathy and ION-style nutrition, I’d like to end with a joke for all the science students who’ve taken the piss out of those of us who are studying arts and social sciences:

what do you say to a science graduate? large big mac and fries, please.

UPDATE: Food for the Brain have responded to my criticisms by revising the page in question. The new text advises that those caring for autistic children “consider pursuing a wheat and dairy free diet which has proven helpful for some, but not all, autistic children. However we recommend you do so under medical supervision, or supervision of a dietician or nutritional therapist to ensure that suitable replacement foods are included that ensure your child achieves optimal nutrition.” While I haven’t had time to go over the page in detail, this is a clear improvement on the previous advice - and is very welcome.
This means that the version of the Food for the Brain site referred to in the below post is an older (out-of date) version of the site.

1Towards the start of the year, the Independent on Sunday reported allegations that a Food for the Brain intervention lead to an autistic girl suffering sleep problems and weight loss1. I’ve already pointed out that Holford’s Brain Bio Centre’s online advice for kids with ADHD could also cause problems - because it advocates an overly restrictive diet2. However, given the previous problems that Food for the Brain has had, you’d think it would be extremely careful not to give any potentially harmful advice to autistic kids and their parents. Well, you would expect this…

Actually, Food for the Brain’s ‘Action Plan’ for autistic children advises that they “avoid the remove the likely culprit foods such as wheat and dairy from the diet. In any case, avoid additives and preservatives3.” Now, I’m not quite sure what ‘avoid the remove’ means - there are enough typos on Holford’s websites that you do wonder whether Holford and colleagues have got their brain-boosting supplement regimes quite right. However, it sounds like Food for the Brain is advising that large numbers of foods should be eliminated from the diets of autistic kids.

There is no mention of the need to seek the advice of a properly qualified medical professional - or any medical professional - to monitor the effects of such a radical intervention. However, when putting children on a restricted diet you do need to be careful that they get the Calories and nutrients they need in order to grow and thrive.

Just to be clear what I find so worrying, I’ll recap out some of what happened around Food for the Brain in the past:
- Food for the Brain put an autistic girl on a relatively restricted diet (despite knowing that she was already, before being put on this diet, “a very poor and fussy eater4“). In January, the dietician Catherine Collins alleges that diet this made her lose weight and suffer sleep problems5.
- In a March ‘clarification’ in the Independent on Sunday, Holford acknowledges that “[t]he temporary weight loss may have occurred when we put her on a gluten-free diet6“.
- Happily, the weight loss was noticed and the girl was put onto a less restricted diet - which included the reintroduction of wheat pasta. Since this was done, the girl “has…regained the weight she lost7“.
- Still, the Food for the Brain website advises that autistic children should be put on a gluten and dairy free diet, without mentioning the need to seek medical advice and supervision.

It sounds like the girl who was the subject of the Independent on Sunday’s March story may have been ‘lucky’ - her problems were noted, and she was taken off this gluten free diet. I really hope that no children will be harmed by the advice that is currently on the Food for the Brain website - but, if a restricted diet causes excessive weight loss and/or malnutrition, and if the child isn’t being supervised by a competent professional who can act to correct these problems, the risks really don’t bear thinking about…

This was meant to be a nice, light-hearted entry - but to be honest the thought of a ‘respectable’ charity giving out advice that could harm vulnerable kids (even after past experience should have taught them about the need for supervising this type of diet) makes me sick. Perhaps those running Food for the Brain could use the - no doubt considerable - thinking power of their cooperating brains in order to at least remove the dangerous advice from their website. I mean, before we get onto advice which is wrong and/or not backed up by sound evidence, couldn’t they just remove the advice which could lead to children being hurt.

Please.

There’ve been a number of controversial goings on around Patrick Holford’s wikipedia entry in the past few months. He has taken a definite interest in this entry, with Fuel PR (who represent Holford) previously editing the page, and with Holford himself asking subscribers to his e-mail list to edit the wikipedia entry.

A wikipedia user called Patrick James Holford has recently been editing Holford’s wiki entry. Of course, one can’t know whether this is Holford himself, or whether someone has just taken his name - but, if this is the real Holford, it’s interesting that he’s putting what looks like a reasonable amount of energy into revising his wikipedia entry.

As you’d expect, some of ‘Patrick James Holford’s edits are being accepted, others rejected - see the history of the article, for details - but, if this really is Holford, it’s good that he’s taken up a more open and direct approach to engaging with wikipedia. The edits being made by this user are also - to my eyes - more collaborative than previous attempts, and much more ‘in the spirit’ of wikipedia. I can’t help but think that Holford would have got a better reception on wikipedia if he had taken this type of approach to the content of his entry to from the start.

One more thing to point out - this blog entry really isn’t an invitation to go to wikipedia and vandalise Holford’s entry. The more people who contribute to wikipedia the better - find details on how to contribute here - but please be nice and don’t break anything…

Right - some disclosure of my interests first. I’m dyspraxic, and a couple of people I care about are dylexic. People often assume that dyslexia and dypraxia indicate a lack of intelligence. This annoys the hell out of me, and is wrong. Children with dyspraxia are “are healthy [and] of normal intelligence“; the same applies to adults with the condition. Dyslexia “can occur despite normal intellectual ability“.

Holford’s Brain Bio Centre, though, does not seem to know this. In their page on dyslexia/dyspraxia, they state that people with these condition should be tested for heavy metal toxicities because a “number of studies have proved the connection between high lead levels and low intelligence and in addition Copper is another toxic element that has been reported to be high in dyslexic children“.

Firstly, if you’re going to imply that I’m of subnormal intelligence, please try to do so in a well-constructed sentence - otherwise, my irony meter gets overloaded. Secondly, though, this claim is clearly both wrong and offensive: the Brain Bio Centre is assuming - without good reason, or any evidence - that two large groups of people are of subnormal intelligence. This is a remarkably stupid thing for them to assume: maybe Holford and his colleagues should consider testing themselves for heavy metal toxicity, especially if they take the copper-containing supplements sold by Holford’s Health Products For Life (see below)

One more thing to note is the claim that “Copper is another toxic element that has been reported to be high in dyslexic children”. There is some evidence for this correlation - although Pubmed fails to show up evidence that copper in any way causes or worsens dyslexia. However, it’s interesting to note that Holford’s Health Products For Life webshop sells three products containing the ‘toxic’ element copper. I think that my irony meter has just exploded.

Sorry to keep banging on about this - but I’ve just found another piece of Holford’s writing where he describes his BMJ Rapid Response as a “reply in the BMJ“. This really could be misleading.

Hell, I’d love to have a reply article in the BMJ to put on my CV. However, Rapid Responses are quite different from articles: the BMJ puts nearly everything that’s submitted onto their website, and does not subject Rapid Responses to peer review etc.

Interestingly, the Sunday Times journalist Brian Deer warned the BMJ in 2005 (in a Rapid Reponse) that “countless BMJ rapid responses…have been routinely lifted wholesale and republished across the web as apparent content from a medical journal“. Whether or not Holford is trying to mislead his readers, it would be easy for readers to misinterpret his references to a BMJ ‘letter’ and ‘reply’ as claims that the BMJ published his response to Goldacre as a letter or as a full article. The BMJ did not do this.