Earlier today, Eusebius McKaiser invited me to join him in a half-hour conversation on critical thinking – how we should do it, and how we fail. Seeing as I happened to be in Johannesburg, I was able to join him at the PowerFM studios for the conversation that ensued, which proved to be far more interesting – for me, at least! – than the more typical interview by telephone. For those interested in the topic, the Soundcloud podcast is embedded below.
That title, because I do think it an implausible and potentially unreachable goal to convey (relatively) subtle points about epistemology when the points in question relate to an emotive topic, namely our health and diet.
According to a few folk on Twitter, my blog posts on the topic have amounted to “rabid attacks”, which I find distinctly odd, seeing as the only ad hominem – and emotionally animated rather than merely critical – engagements I’ve seen have been directed at those of us who dare to challenge anything related to the LCHF diet and its proponents.
So, in bulleted points to try to minimise confusion, here are my concerns and positions. These are the same concerns and positions I’ve expressed from the start, contrary to what some “rabid” comments have claimed in response to my posts and columns on the topic.
- Regardless of the efficacy of the LCHF diet in treating various conditions, and regardless of the truth or falsity of hypotheses assumed by the LCHF diet, we should all have a concern for good scientific thinking, and clear reasoning in expressing the conclusions we’d like to see adopted. Science does not work in absolute truths – it’s an inductive process, whereby we chisel away at falsehoods to arrive at a clearer understanding of what’s most likely to be true.
- That project of triangulating on the truth is harmed by expressing scientific claims in absolutist language, and by creating movements akin to cults, where people are more likely to forget that anecdotes aren’t data, that being wrong in the past doesn’t guarantee you’re right now, that emotional commitment leads to confirmation bias, and so forth.
- My criticisms of Noakes have mostly been that – whether or not he’s right – he doesn’t present his case in a way which demonstrates sound scientific reasoning. We reveal ourselves when we “show our working”, and it’s not reassuring to see anti-vaccine quacks and evolution-deniers quoted approvingly when arguing for LCHF. It demonstrates a desperation to make a case, and a lack of sound judgement.
Likewise, not focusing on the details, or the evidence, is a bad sign. Take this tweet as example:
— Tim Noakes (@ProfTimNoakes) March 16, 2014
- It references the UCT Health Sciences Centenary Debate between Dr. Jacques Rossouw (my father) and Noakes. But notice how it references it – by dismissing me as a latecomer who somehow rushes in to defend my father’s cause. However, the evidence shows that I was writing about this 9 months before that debate, and that Rossouw père hasn’t been engaged with Noakes at all for around 20 years, and only got involved in this debate on an invitation from the Medical School when an ex-colleague had learnt that he was coming here on holiday. It misrepresents (a truly rabid critic might even say “lies”) to further a particular narrative.
- Likewise, it’s misrepresentation to tweet (as Prof. Noakes regularly does) links to Noakes’ SAMJ article criticising the WHI study that Rossouw directed without acknowledging that there were at least two responses to the Noakes article, arguing that his criticisms are misguided.
- A summary of the problem might be this: Noakes’ audience is primed to believe, and primed to think that critics are deluded, because of the narrative they’ve been told, and because their anecdotal experience (in the short-term, at least) confirms that narrative. And then, the way in which Noakes responds to critics (e.g. “I ignore what I consider not to be evidence“) seems to do little to help them think critically about science, because criticism starts – and sadly, also ends – with the charge that traditional views of diet are deluded.
- It’s entirely possible that the long-term harms of high meat or fat consumption are overstated, and therefore that Noakes is right. But I can’t imagine him saying that it’s entirely possible that we don’t yet know if there are long-term harms from following his advice, or that it’s entirely possible that a moderate diet, involving a focus shift away from any single or particular macronutrients, might be best for most people. Nothing seems possible, except that he’s right.
- Then, the LCHF crowd get relationships and potential taint utterly wrong in any case – just because someone works for “Big Food”, the FDA, the South African Heart Foundation or whatever – or is someone’s father/son – doesn’t absolve you of the need to make and respond to arguments. Sure, the connections can lead to the increased probability of some sort of bias, but you still need to show the bias, and not simply evade challenges by asserting it.
I’ve written at length about logic, epistemology, scientific reasoning, anecdotes and their irrelevance, and other issues to do with Noakes’ warrant for presenting his case with the degree of certainty that he does. I’ve said very little about the diet itself, because that is not my focus – and it doesn’t need to be my focus.
The retort that there is “bad science” on the other side is not compelling, in that it’s a) bad science (if it is) mostly because the LCHF people think it reaches entirely the wrong conclusions; and/or b) because it uses poor data. My accusations of “bad science” are premised on the selective quotations, dubious authorities cited and so forth as demonstrated in social media, rather than being about “bad science” in the sense described in (a) and (b) above.
To capture the essence of the only things I have ever said about diet specifically
- I’m concerned about the affordability of the LCHF diet for poorer populations.
- I can see how people might be concerned about animal welfare and an increase in the farming and killing of animals. I eat meat, but think it’s a moral failing that I do – and furthermore, I think that the immorality of meat-eating will be the subject of a moral consensus in my lifetime.
- Independent groups like the Harvard School of Public Health continue to caution against excessive consumption of saturated fat.
- I’m not at all persuaded by what LCHF folks assert as evidence of the failure of the so-called “prudent diet” – first, because it’s not at all clear that people have ever been eating that way (in general); and second because it caricatures dieticians as having recommended a diet that they claim they aren’t recommending at all. A series of blog posts at Nutritional Solutions are worth reading in this regard.
- In short, the increase in obesity and the like still seems mostly explicable by the advent of television, increased access to motorised transport, desk-bound lifestyles, and excess consumption of food.
- Yes, it certainly seems true that fats (in general) have been demonised far more than they should have, and that some of us might have started eating too much of other things (including carbohydrates, especially in the form of sugars) to compensate for a flavour-deficit after shunning fat.
This doesn’t, however, automatically lead to the conclusion that carbohydrates are in general bad, nor to the conclusion that we need no longer be at all concerned about the long-term effects of a diet with significant levels of saturated fat. “Real food” is good, sure – and refined carbs are “bad”. And what that means is, when you carry on eating your modest portions of a balanced diet (which is surely what you eat, right?), you should continue to be wary of including too many processed and refined foods.
That’s what I’ve always been told. What’s “new” is that fats aren’t as bad as we thought, and I (along with many of you, no doubt) were misinformed when we were told that they were rather evil. The truth is probably in the middle somewhere – and why replace one exaggerated position (“fats will stop your heart!”) with another (“carbs will give you diabetes!”).
As Oscar Wilde had it, “the truth is rarely pure and never simple”.