The text below was submitted as a letter to The Cape Doctor, a South African Medical Association publication for medical professionals in the Western Cape. In the August 2019 edition, Marika Sboros includes my name in some of her fantastical musings, and I felt that a rebuttal was in order.
Given that the publication is typically only seen by its subscribers, I post the text of that letter here also, for the record. The edition in question (pdf link) is available on samedical.org, and a backup is stored here on Synapses too.
It’s been a few months since I last posted anything about diet and Prof. Tim Noakes, but being reminded of the hearing that’s set to resume next month led me to check in on his Twitter echo chamber, which in turn leads to my presenting these few morsels to you.
First up, Austin Bradford Hill, who (according to Noakes, at least) taught that association only provides evidence for causation when a study’s Hazard Ratio (HR) is above 2.0. With the assistance of this factoid, Noakes has been dismissing inconvenient results with quips about “Bradford Hill turning in his grave” and so forth.
The Hill paper that Noakes cites (the text of a speech in this case) is indeed very good. It cautions us that systematic errors are prevalent enough in our research that we should be wary of placing too much faith in statistical significance as a guarantee of anything, and that health-related interventions need to be thought about carefully, in light of potential costs and benefits (rather than only with reference to what the evidence tells us).
And then, there’s this:
None of my nine viewpoints can bring indisputable evidence for or against the cause-and-effect hypothesis and none can be required as a sine qua non.
The point, of course, is that Hill is here being misrepresented as a dogmatist, in order to give Noakes another of his stock-phrase putdowns (“cognitive dissonance”, “The Anointed”, “follow the money”, “go ahead, make my day” and so forth).
The misrepresentation is significant also because in this particular case, Hill might not be on Noakes’s side of the argument at all. As argued in this Phillips and Goodman paper, one of Hill’s central points was that “we need to consider more than the degree of certainty that there is some health hazard, and act based on the expected gains and losses, with or without statistical certainty.”
So, if it’s still the consensus view that limiting saturated fat (or rather, replacing it with unsaturated fat or whole grains rather than refined grains) is a good idea to minimise cardiovascular disease risk, it seems to me that Hill would accept the “violation” of his (non) rule for the sake of prudence.
Don’t get me wrong – of course it’s true that it’s difficult to establish causation from association. But it’s also true that absence of evidence is not evidence of absence – and that we need to apply our standards consistently, and honestly.
Hill didn’t give us a rule (that’s the honesty bit), and even if he had done so, I’m pretty sure that a trawl through Noakes’s timeline would give us many examples of him uncritically linking to pro-Banting literature that violates the rule (that’s the consistency bit).
Speaking of consistency, and the Banting-brigade’s fondness for accusing critics of being in the pockets of Big Potato (or compromised by some nefarious interest), I wonder how they feel about Nina Teicholz, lobbyist extraordinaire, being bankrolled by a billionaire?
I don’t think it necessarily a problem at all – as I’ve said in previous posts, we need to separate the claims from the funding – but if conflict of interest is a problem (as Banters claim), you don’t get to ignore it just because you like what the person is saying.
To repeat a point I’ve now made many times over the years, the issue for me is not the science – that’s evolving, as it tends to do, and there are still many unanswered questions related to diet and its effect on health, weight and so forth. The issue I am concerned with is misrepresentation, cherry-picking, logic and the substitution of soundbites and celebrity for scientific rigour (on that, here’s a good piece by Sarah Wild).
Recent studies suggest that low carbohydrate diets appear to be safe and effective over the short term, but show no statistical differences from control diets with higher carbohydrate content and cannot be recommended as the default treatment for people with type 2 diabetes.
The authors also note that “passion in science is an infallible marker of lack of evidence” – and while I think that overstates the matter somewhat, it’s again a useful rule of thumb.
Someone linked my tweet of that study to Noakes earlier today. His response perfectly captures the problem, and that response is a) to ignore it in favour of cherry-picked alternatives; and b) to suggest malice or bias on the part of those who disagree with him.
To answer the “why” in that last tweet: because I’m linking to the review of RCTs mainly to demonstrate that the evidence is contested, and that there’s no room for dogmatism in this debate (or in any scientific debate that isn’t settled).
If there was as prominent and influential a scientist as Noakes arguing as dogmatically on another topic that I’m interested in, articles on that topic would attract a similar amount of attention, at least from me.
The “why” is of course not sincere at all, but instead simply an opportunity for disciples to dismiss contrary evidence as conspiracy. If you’re looking for a textbook example of motivated reasoning, the Noakes timeline is pure gold.
On the last night of January, I participated in a rather interesting hour of radio, during which Hlomla Dandala hosted a interview with me and someone claiming to be a faith healer. The faith healer’s name is Pastor Louisa, and you can find some information on her ministry – which includes curing people of AIDS – on her website.
I do have a recording of the show, but haven’t yet found a way to convert it into something that plays outside of the TuneIn Radio app on my phone (informed advice on this is welcome) – if I do get it converted, I’ll be sure to post it here.
What became clear fairly on in the show is that Louisa is not a charlatan, in the sense that she’s knowingly exploiting others. She was desperately sincere, and also, unfortunately, sincerely confused. When invited to facilitate a miracle over the phone to someone who called in, she engaged in a few minutes of shouty, enthusiastic prayer and exhortations to be confident and inspired, after which she asked the caller whether she “felt better”.
Yes, said the caller. I then asked – “so, does that get added to your list of miracles performed?”. Yes, said Pastor Louisa. On those weak standards, all of us perform dozens of miracles every day – just figure out what language people like to hear, or what buttons they like pushed, make them happy, and then claim to have performed a miracle!
Also, she made it clear that she never tells people to stop taking their medicine. Dandala asked her how she knows whether it’s the prayer or the medicine that heals… and the predictable answer that she gave was that she “just knows”. As far as I can determine, then, she gives her god the credit for the job performed by modern medicine.
You’ve heard how this (faith healing) works before, I imagine, or rather, how it doesn’t work. On the recommendation of Dan Dennett, I watched the documentary Marjoe a few years back, and it’s a wonderful expose of charismatic preachers and healers, involving Marjoe Gortner taking a documentary crew behind the scenes of his final revival tour, held after he had already lost his faith. Watch it if you can, but basically, if people want to believe something strongly enough, it’s difficult to stop them doing so.
The difficulty in talking to Louisa was in resisting the impulse to mock, but instead to feel sympathy for her confusion, and the desperation of those who take her seriously. I failed in this effort at least once, when she spoke about how she had to stop talking to us because she was out in the open, under a tree, and it was cold (this was late at night). I suggested that a miracle might sort this out – after all, if she could cure Aids, what’s the problem with a little heating?
Failures of good grace aside, these people can be dangerous, especially in communities we don’t often hear about, where faith healers and other quacks can do their thing without being exposed to scrutiny. Communities like the Amish are a similar problem. And the overarching problem we all have in a constitutional democracy is in striking the balance between objective application of the law and respecting the various freedoms we believe people are entitled to, like subscribing to and practicing a religion.
For adults, there’s less of a concern regarding people being free to harm themselves than there is for children, who can’t be expected to know any better. But desperation, and poor educations, mean that adults are also sometimes more gullible than one would like, which is why it’s incumbent on all of us to speak out against quackery where we find it, while still trying to avoid being gratuitously cruel to those we criticise.
And those of us in positions of authority should perhaps be most careful, because their trust is vested in us, and they spend money, time and attention on us.
Someone getting a lot of attention right now is Professor Tim Noakes, as he goes around the country giving talks and radio interviews to promote the book he’s recently co-authored, The Real Meal Revolution. During a recent interview with Redi Tlhabi, he informs listeners (at 38m40s) that there is “absolutely no risk” involved in cancer victims trying the ketogenic diet, because it’s proven that starving cancer of carbohydrates is an effective treatment.
Well, yes, it can be. But as he so often does, he’s cherry-picking, or simply believing in the version of “science” that suits his agenda. Because according to the Sanford-Burnham Medical Research Institute, and other sources,
Many scientists have tried killing tumors by taking away their favorite food, a sugar called glucose. Unfortunately, this treatment approach not only fails to work, it backfires–glucose-starved tumors get more aggressive.
This is only true for some glucose-starved tumours, to be sure, but it still means that saying “absolutely no risk” is absolutely untrue, and that Noakes is giving advice – to an audience of thousands – that stands a good chance of harming a listener who happens to have the sort of cancer that responds aggressively to a low carbohydrate diet.
As I’ve said many a time, this isn’t the approach of someone who is a responsible scientist. But, just like the faith-healer, I think he’s utterly sincere, and utterly committed to fostering our good health. More the pity, then, that he’s unable to see how his religious fervour might end up achieving the opposite goal, at least for some. And how – consistently – he’s wreaking havoc on basic principles of critical reasoning, and setting a terrible example for budding scientists everywhere.
Evidence based medicine is the conscientious, explicit, and judicious use of current best evidence in making decisions about the care of individual patients. The practice of evidence based medicine means integrating individual clinical expertise with the best available external clinical evidence from systematic research. By individual clinical expertise we mean the proficiency and judgment that individual clinicians acquire through clinical experience and clinical practice. … By best available external clinical evidence we mean clinically relevant research, often from the basic sciences of medicine, but especially from patient centred clinical research into the accuracy and precision of diagnostic tests (including the clinical examination), the power of prognostic markers, and the efficacy and safety of therapeutic, rehabilitative, and preventive regimens.
In short, EBM is about integrating the best available research knowledge with the expertise of clinicians, who might – and often do – spot something that a model or a manual might not recognise as significant. As much of a naturalist as you might be – and I’m a very committed one – raw data exists in a context, and the context might often be a significant clue in telling you what data are relevant, and how they should be interpreted.
So I share some of Dr. Malcolm Kendrick’s concerns, when he writes that “EBM is now almost completely broken as a tool to help treat patients” thanks to the “evidence” being susceptible to corruption by vested interests, and pharmaceutical companies in particular. If you fund enough research, and suppress results that you don’t like, it’s certainly possible to end up with all the “evidence” pointing in a favourable direction. Favourable for you, that is, but not for the patient.
But the fact that something is funded by a pharmaceutical company doesn’t guarantee bias. There’s a difference between being cognisant of potential biases, and writing something off in advance, just because of whence it came. That sort of pre-emptive dismissal is a logical error called “the genetic fallacy“, and you can tell when it’s being committed if someone stops paying attention to the evidence at all, or starts claiming that they don’t need to even bother doing so. Like this, perhaps (from Kendrick’s post):
Some years ago I stated that I no longer believe in many research papers that I read. All I tend to do is look at the authors, look at the conflicts of interest, look at the companies who sponsored the study, and I know exactly what the research is going to say – before I have even read the paper.
I have also virtually given up on references. What is the point, when you can find a reference to support any point of view that you want to promote? Frankly, I do not know where the truth resides any more. I wish to use evidence, and the results of clinical studies, but I always fear that I am standing on quicksand when I do so.
We are at a crisis point. Medical research today (in areas where there is money to be made) is almost beyond redemption. If I had my way I would close down pubmed, burn all the journals, and start again, building up a solid database of facts that we can actually rely on – free from commercial bias. But this is never, ever, going to happen.
It’s rather alarming to see the person responsible for writing The Great Cholesterol Con – and for encouraging most of us to stop taking statins to lower cholesterol – professing “I do not know where the truth resides any more”. (If he really means that, a career in anthropology rather than medicine might suit him better, I’d suggest, in that he’s already learnt a key mantra of the field.)
Another peculiar thing you’ll find on his website represents quite a cunning stratagem. You see, he’s talked himself into a bit of a bind with this “don’t trust The Man” stuff – if he ever wants to sell you something like a drug, how could he offer you “evidence” in support of it’s efficacy, assuming that he or someone else with a vested interest was involved in that research?
Easy – by redefining what conflict of interest means. For him only, mind you – not for others, where it means that you can’t trust them, and don’t even have to read them to know that you can’t trust them. In his “Disclosure of Interest” page, he notes “I have become the medical director for a company making a heart health supplement called ProKardia”, for whom he does paid consultancy work. And here’s the cunning bit:
If I do write about ProKardia or any of the ingredients in ProKardia, in a positive light, you need to know that I have a financial interest. I did not use the word conflict of interest in this statement, as I do not believe I have a conflict. I have become involved in developing, and using, a product that I entirely believe to be a good thing.
Got that? He has a financial interest alone, but no conflict. Authors of papers with connections to something he doesn’t trust, or research sponsored by pharmaceutical companies, always represent a conflict – and you don’t even have to read the paper in question to know this. (Which, amusingly, means that even if they were to try to insert the same Humpty Dumpty clause into their papers, Kendrick would never read that either.)
I say “Humpty Dumpty clause”, because the book Alice in Wonderland contains this fabulous line: “‘When I use a word,’ Humpty Dumpty said in rather a scornful tone, ‘it means just what I choose it to mean — neither more nor less.'”
It’s the same causal relationship to what words – and evidence – means that allows for claims that sugar is addictive (as addictive as cocaine, according to some), or that Harvard have endorsed low-carb high-fat diets. They haven’t – they’ve just said that carbs can sometimes be worse than fats, particularly the “bad”, saturated fats – yet the LCHF proponents cherry-pick this as support, even though the same group are explicit that the type of fat matters, and that animal fats remain something to be cautious about.
Or, it’s this casual relationship that allows for claims that Sweden has officially adopted the LCHF diet, even though the report – now finally available in English (the summary, at least), though that didn’t stop English speakers like Tim Noakes from relying on blog sources as authoritative on what it said – actually says (my emphasis):
in the short term (six months), advice on strict or moderate low carbohydrate diets is a more effective means of achieving weight loss than advice on low fat diets. In the long term, there are no differences in the effect on weight loss between advice on strict and moderate low carbohydrate diets, low fat diets, high protein diets.
I realise that this is just one element of the debate, which includes diabetes, heart disease and so forth. But these are two examples of scientists cherry-picking data that happens to support something they want to argue for – or that can be made to appear to support it, so long as you whip up enough hysteria, or persuade them that there’s some conspiracy afoot.
As Mark Wallace points out in piece for The Guardian on “addictive” sugar, “if the issue is people failing to act responsibly, then it won’t be rectified by treating them like children”. To that, we can add “treating them like fools”.
And when the same people doing the cherry-picking are giving themselves licence to simply ignore research they don’t like, and to dismiss conflict of interest issues (in their case, but not for you) with a regal wave, they stop being scientists, and start becoming shills.