I'll start with my question: Do you agree with Melissa McEwen's critique of Jack Kruse's (mis)use of evolutionary biology?
I should note that I am a fan of both McEwen and Kruse.
McEwen's blog post is here:
McEwen accuses Kruse of equivocating between two views of evolution - one static, the other malleable. She writes, "Therein lies an essential paradox - on one hand our genes are “paleolithic,” but on the other they are malleable simply by thinking differently."
Here are some initial thoughts toward answering my question.
I'm pretty sure that everybody who studies and thinks about genetics these days distinguishes between (i) the underlying DNA sequence - which often underlies 'static' views of genetics - and (ii) changes in gene expression that can be inherited by the previous 1-3 generations - this is the realm of epigenetics, which often underlies the 'malleable' view of genetics. Yet both the genome and the epigenome have static and malleable features that are relevant to us as seekers of health.
Over time both genes and epigenetics evolve - the DNA sequence evolves, but the nature or pattern of shorter term changes in gene expression also evolves.
My understanding is that Kruse believes that cold adaptation opens up an evolutionarily-old metabolic pathway that lies dormant in - and is thus available to - all of us. He made similar 'old pathway' speculations when he talked about rewiring the hypothalamus in the leptin reset series.
So epigenetic changes are short-term and thus not stable over 30+ generations. Yes, however, changes to the nature of how epigenetics works can and, in fact, must reflect the long-term evolution of our epigenome. There is a difference between (i) the evolution of the epigenome which delimits the scope of possible epigentic effects, and (ii) those epigenetic effects. The former evolves over the long term, the latter changes over a small number of generations.
My understanding is that epigenetic changes begin with changes in gene expression that occur in response to environmental inputs of one generation, and that these changes can transfer to the next 1-3 generations in the form of altered probabilities in gene expression. The thought that 'might just change your DNA' is the first generation of change in epigenetic gene expression.
I am clearly not an expert in genetics or epigenetics (nor do I think that McEwen or Kruse are). However, I see a pretty intuitive - though perhaps charitable - interpretation of Kruse that saves him from the charge of equivocation. Perhaps he is not 'having it both ways' - rather, he is just talking about the genome and epigenome as most do: Both 'systems' evolve, both effect probabilities of gene expression, and both thus have static and malleable features that are worth speculating about because they might be relevant to achieving health.
What do you think? Do you agree with Melissa McEwen's critique of Jack Kruse's (mis)use of evolutionary biology?
You have no idea how hard that post was to write. I mean, it's so hard to read Dr. Kruse's writing and find consistant threads in it. He has references on the bottom of some post, but mostly they do not correspond to things in his posts that I wanted to check.
I have several more posts to write, but help me out here. I mean, Eric, can you find any evidence that epigenetic adaptations to the cold of 3 billion years ago are still conserved today? Of course epigenetics affects evolution, my point is that they are not conserved and they are not as malleable as Dr. Kruse makes them out to be.
I do have a post in the works on reasons why Dr. Kruse's theories do work for some people. I would note that Art De Vany has been touting almost the exact same recommendations for years. That doesn't surprise me since Dr. Kruse is a known plagiarist. Cold adaptation might work for you, but probably not for the reasons that Dr. Kruse says it works.
I will also say that some paleo bigwigs who are probably more respected than I am have a statement on Kruse in the works because they are deeply deeply concerned. I wish I could quote them.
Thermal hacking has a VERY long history and also has been known to be unsafe in certain situations for certain people.
I will also say that I have access to all those nice journals because I am enrolled in an evolutionary biology program, though I do not intend to complete it because I would like to enroll in a PhD program hopefully studying genetic adaptations to diet. I am not a geneticist and have so much to learn, but I have a year of college level genetics classes under my belt at this point and many more years of evolutionary biology classes, so I'm not really a layman or an expert at this juncture. But MDs currently are not required to take ANY ev bio or genetics now, so I highly doubt that Jack has ever done such a class.
Dr. Kruse should either commit to being really serious about learning evolutionary biology OR he should be like Dr. Rosedale and not rely on questionable just-so stories with little evidence. I think he just enjoys grand narratives.
Two things: First I will take Melissa over Jack on the question of evolutionary biology every day of the week. Second, via Jack's TEDxNashville presentation, we learned that he intentionally gained 25 lbs, had elective plastic surgery without anesthesia and after injecting himself with MRSA, and went home and relieved his post-op pain with ice.
He is now practicing his protocol (save for the MRSA presumably) on his patients.
The man is committed to his vision that's for sure. But the Vegas odds on whether he will actually be committed may not be in his favor!
I could give a rat's ass as to who is "correct". The question for me is "Will cold thermogenesis+ketogenic diet+ seasonal eating help me finish my thirty year battle with fibro/cfs/adrenalfatigue/hypothyroid/depression/severe allergies/" After three weeks, my tentative opinion is the guy is on to something. I feel better. The pissing match is annoying! I'll update weekly if anyone cares. The program costs nothing.Let me repeat,nothing! The side effects= maybe the cold I got on the third day. Also I've hurt my back/neck twice because the cold adaption made me stronger, so I added weight and overdid it.I've been lifting weights since 1974.There is something to the "COLD". I don't care if it has anything to do with evolution or not!.....Have we all forgot about the concept of (n=1). Isn't (n=1) the basis of evolution?
I think the fact that you have to do so much interpretation to make sense of what Kruse says is not a point in his favour.
You're right that neither McEwan nor Kruse are experts in genetics*. The difference is that McEwan knows she is not an expert, and therefore restricts her claims about genetics to what comes out of reputable scientific literature. Kruse apparently thinks he is an expert, and makes radical claims without the reputable science to back it up. In the words of Daniel J. Boorstin, "the greatest obstacle to discovery is not ignorance - it is the illusion of knowledge".
Admittedly, I'm seeing this mainly through the lens of Melissa McEwen's blog, but I've never heard anything but skepticism, from any paleo blogger I respect, about Kruse's theories. For example, Paul Jaminet seems to tacitly admit Kruse is a crank, but refuses to directly call him out because he doesn't want to be unpleasant.
*But see Melissa McEwan's comment below. McEwan does have academical credentials in the field of genetics, which Kruse lacks completely, so far as we know.
I didn't read your full question because I'm not interested in anything having to do with Kruse. His target audience seems to be people that don't get it and assume that complicated = smart. Seems to me that he likes to pretend to be smart but he's not.
There are obviously a lot of Kruse skeptics and I think Melissa's article was just putting some actual material down rather than simply calling him a quack.
I think that the nature of Kruse's writing, being poorly written and substantially long, is going to inhibit anyone that could actually explain why it is wrong from wasting their time trying to do so (if such a thing is even possible).
My opinion of it is that he's probably wrong. Key word: probably. He could end up being onto something, but it's very unlikely. He tends to think that because a thought makes sense that it must be true. The banana in winter and "he's a mammal, you're a mammal" logic are horrible for his argument. But the strength of an argument can't always predict truth or fiction.
Is a leptin reset diet good for some (or maybe even a lot of) people? Probably. Are there benefits from exposing your body to cold? Yes. But that doesn't mean that a positive result from those things implies that what he says is factual.
It's probably just going to take time. As time goes on and his methods end up not producing the miraculous effects he claims, that's when we can definitively say he's wrong. Until then, you can never say for sure that the guy's absolutely not onto something.
I dont know or care- I follow what has been succesful for me and try out a few things that seem to fit but like Dr Atkins who still gets kicked around, it seems those close to the truth and outside the mainstream are always under the gun. Must be a reason for that.
In my view both McEwen and Kruse seem to struggle with the definitions of genetics and epigenetics in terms of evolution.
Firstly, in the current model, evolution is mediated by changes in the genome - not the epigenome. Genetic changes take many years, sometimes thousands and tens of thousands of years for changes in genes to have a phenotypic effect.
Epigenetics mediate gene expression changes within individuals and some epigenetic inheritance is evident parentally and grand-parentally (e.g. Dutch hunger winter).
There is no evidence of epigenetic information transmission extending further than a grand parent, i.e. 2 generations in humans.
Epigenetics is also why your neuron cells and muscle cells, whilst having radically different physiological function and gene expression, share the same genome.
Take home message: epigenetics is concerned with transient gene expression changes, intra and intergenerational reversible adaptations.
The biggest and most unappreciated confounder - that both McEwen and Kruse have failed to mention - is the effect of our other genome - that of the thousands of bacterial species that colonize the entirety of our gastrointestinal (GI) tract from birth. It is this genome that is capable of an astonishing degree of evolutionary adaptation and which also is able to dramatically influence the interaction with our environment.
I think McEwen did a good job in her critique. I don't know enough about evolutionary biology to make a statement on his accuracy. I do know enough to say that if Dr. Kruse is going to write about these ideas, he needs to make a better effort at making them clear to the audience. I think everyone would be better served if he provided more support from scientific literature.
Generating a hypothesis based on evolutionary biology (whether the biology is accurate or not) doesn't mean much without support based on our knowledge of our current biology. Even if he is right, it doesn't look good for the paleo community.
The doctors I worked with also had more clinical experience than Melissa, medical training, and actually worked with ill people on a daily basis. And I'd trust HER opinion over 95% of them.
It's like Robb Wolf said at the Ancestral Health Symposium: he was considering the field of medicine until he started having to deal with doctors--after that, he didn't want to be associated with them anymore.
Kruse is a brilliant guy, no doubt. But that "doctors are infallible because they're doctors" ideology is the type of absent-minded, starched mitochondria thought process we want to avoid. Less we all become damn 811 indoctrinates...
...eat more fruit...Dr. Graham looks healthy...durianrider knows...something...drool
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