As I made clear in my first Response to Denise Minger video, Ms Minger lifted major ideas from my Ancel Keys videos and passed those ideas off as her own, without any effort to cite me properly. Additionally, she left the impression these ideas in her blog were corrections of the material in my videos. She said, “In fact, it was his glossed-over portrayal in a recent series of anti-paleo YouTube videos that inspired me to write this post.” Ms Minger has now responded to my complaints in her comments section. These responses deepen an impression of a lack of high standards. Ms Minger said the following:
“For what it’s worth, I corresponded with Plant Positive over email after this post was up, and in the time between this post going up and now (3 months?) he has never asked me to attribute his name to anything in this post, nor otherwise expressed concern with what I’ve written in terms of “intellectual dishonesty.” If he contacted me with any unhappiness about this, I would gladly add any addendums necessary to clarify his role in bringing the Ancel Keys “myth” to the fore.”
As Ms Minger knows full well, it is necessary to cite at the time of publication. It is not the responsibility of the originator of borrowed research or ideas to monitor the use of his work on the Internet and to request that a proper citation be given. Likewise, a plagiarist cannot reclaim a presumption of integrity simply by providing a reference AFTER BEING CAUGHT. It doesn’t work like that and Ms Minger knows it.
Moreover, as I stated in the video, it is incumbent upon one making reference to another’s work to summarize the ideas of the referenced work and its importance to the new work. Should that not be appropriate, an in-text citation should be placed next to each statement utilizing the referenced work. Even now, Ms Minger has not really done this but for one minor instance (Mexico’s death certificates). She now states:
“(Note: This post was inspired by the “Ancel Keys” section in a recent series of paleo-challenging YouTube videos, which I may critique in the future. The anonymous videomaker “Plant Positive” highlighted some important misconceptions about Keys and his research that I’d like to broadcast to a larger audience, but didn’t address some equally important points tangled in the Keys saga, and likewise made some arguments I believe are incomplete or misleading. This blog post is an attempt to address those misconceptions in a more balanced and thorough way, and provide a broader context for how we view the infamous Mr. Keys.)”
Observe that Ms Minger still does not say what she has taken from my work, only repeating that her blog post was “inspired” by my videos. This is totally inadequate and I shouldn’t have to say so. She purposefully leaves the impression she has contributed something of equal value to my work. In my new videos, I make clear this is not the case at all. And again, she says I had somehow been incomplete or misleading. The fact that she still insists on criticizing my work in her reference– without specifics and even as she is being pressured by public shaming to give me appropriate credit – reveals once again her difficulty with academic integrity. She needs to cleanly cite the any content of my work she is using. Her statement of her negative opinion does not constitute a proper citation. Ms Minger then copied and pasted her criticisms of my original videos, criticisms I answered in detail in my new videos. She seems to be pretending I have not answered these challenges. How she feels comfortable doing this, I have no idea. It is apparent she is not willing to engage me honestly; she only wants to appear that she is. It is difficult to know how to respond to such an individual.
Regarding her mention of her email exchange with me, she has placed me in the uncomfortable position of wondering whether it is appropriate to publicly discuss private emails. To the detriment of my complaint here, I will respect the privacy of those emails. Suffice it to say, she did not raise the issues of either my critical videos of her or her Ancel Keys post. I will allow one quotation of myself here. I said, “I am preparing a video response to your comments about my videos. Your criticism is public, so my reply to it will be as well. If you would like to communicate privately after that, that works for me. I reply to everyone who messages me.” Why did I not ask for appropriate citations then? First, as I said, that is not my responsibility so the question is beside the point. But frankly, I found it so shocking that she would take my material and represent it as her work only five days after having acknowledged she’d seen it that I thought that it was more important to expose that behavior than to receive timely credit for my work. Her offer to send me papers I could not access, along with her unexpectedly friendly manner, suggested to me she wanted to defuse the irritation she surely knew she caused me. Think about it: I put up four videos criticizing her China studies nonsense, she took my Ancel Keys material and represented it as her own, and mentioned neither of these in her unsolicited personal messages to me. She instead offered her help retrieving journal publications (to have advance notice of future projects of mine, perhaps?). Additionally, she made comments under my video 63 as follows:
“My own diet is about 90% plants, so if I have biases associated with my own food choices, they should be favoring the plant kingdom.”
“I agree cholesterol denialism (in the sense that blood lipids are ... ... unrelated to heart disease) is a problem”
I believed Ms Minger was trying to win me over a bit so I wouldn’t call her out publicly for her Ancel Keys blog post. This almost worked. Yet in the end, I decided to pull no punches.
As anyone who has seen my “Vegan Propaganda” video, challenging the dogma of the low carb/Paleo crowd carries the risk of getting dragged into an arena of debate without rules. I don’t like being in attack mode. I don’t want to face the torrent of ridicule that T Colin Campbell has received. I would rather be on friendly terms with Ms Minger and everyone else. But the fact is she has sought and acquired a place of public prominence. She has purchased it cheaply by attempting to discredit respected and responsible academics with bogus and manipulative arguments and she has used it to mislead the public about important health matters. These matters are not part of a game. The price for nutritional misinformation is paid in the form of lost productive years, unmanageable medical bills, and lost time on this Earth with friends and family. Therefore, it doesn’t matter that I would prefer to be friendly with her, and it doesn’t matter what further abuse will come my way. There is a greater good that is more important than all that.
Ms Minger ends her new introduction to this blog by once again calling Ancel Keys “infamous”. My videos demonstrate that any demonization of him is not fair, and it appeals to a bias among her readers, a bias created through the perpetuation of a lie. I find this cynical scapegoating of a man who can no longer defend himself to be distasteful. Ms Minger seems to be reacting immaturely and defensively to my videos. She would do better to offer a mea culpa and allow this experience to inspire some fresh self-reflection about what her contributions should be and how she might better use her talents to serve others.
Have you read this far? What did you learn about science, history, or nutrition from my discussion of this matter? I am guessing nothing. This is why I do not expect to be a participant in a long-running exchange with Ms Minger or anyone else. It doesn’t really help anyone. What I’ve done so far is enough. My videos were my effort to provide quality references and support for those who are truly open-minded and curious, and to demonstrate the intellectual bankruptcy of the Paleo/low carb idea and the lack of credibility of some of its proponents. Ms Minger suggests she may criticize my videos in the future. I can now imagine how Dr Campbell may have felt after having gone back and forth with her a bit. At a certain point it likely became clear that he would not satisfy or outlast her. Folks, this isn’t what I do for a living. Unlike Ms Minger and the various other saturated fat and meat apologists, I do not have a book to sell you. I have pressing business that requires my attention. I will not have the time to engage in this further. I have put out some good material for those who are open to it. Realistically, I can’t do much more than that.
Primitive Nutrition 7: A Diet in Your Genes? Part I
As you know by now, the purported superiority of primitive nutrition is premised on the idea that there is particular diet which our hunter gatherer genome requires.
Sometimes it is stated more accurately that our nutritional needs are genetically programmed. This is true, of course. We need vitamin C to prevent scurvy, for example, and the reasons for this can be found in our genes. But nutrition science hasn't needed a Paleo diet idea to figure out what nutrients we need. And make no mistake, regardless of context, Paleo promoters are not talking about nutrients and nutrients only. They are devoted to a diet. Paleo promoters consistently advocate for a specific diet that includes a lot of meat and avoids grains and legumes.
Paleologic is based on the genome. Amazingly, this line of reasoning has even found its way into a proper nutrition textbook. That is why I will now take some time to discuss the genome. Is it possible we have a genome that is so particular about diet?
Thanks to this author, Gary Marcus, we have a very apt term to describe the result of an evolutionary process: kluge. Sometimes you'll see it spelled differently. Marcus takes this term from the technology world.
A kluge is an inelegant, jury rigged solution to a problem.
Of course, the results of evolution are often quite beautiful and elegant, but make no mistake, evolution produces Rube Goldberg contraptions. This is because evolution happens in tiny increments over time, always working from previous inheritance. In evolution, there is never a complete tear-down or bumper-to-bumper redesign. No one began a new design for Paleolithic man from a clean sheet of paper.
Evidence of this goes all the way back to the development of eukaryotic cells. As this paper demonstrates, two billion years has not been enough time for our genome to even integrate fully with itself.
More evidence of our kluge genome comes in the form of genetic material squeezed into it by endogenous retroviruses. This amounts to about 8% of our genome, compared to the approximately 1.5% of our genome used for protein coding.
Knowing that our genome is a kluge, with evidence of this extending all the way back to our beginnings as eukaryotic cells, we can now appreciate that our genome is the product of a long legacy that extends back not just 10,000 years, and not even two and a half million years, but rather two billion years.
This is a good time to introduce you to some important terms in genetics if you don't know them already. This will help us understand the Paleo concept on a basic level.
For our purposes, let's call the genotype the total genetic material in someone’s genome. Usually the term is used in reference to a particular trait that is being discussed. That trait is the phenotype. The phenotype is the functional expression of the genome for whatever trait you are considering.
Looked at this way, Paleologic basically says that we have a stone age genotype - that is, we have stone age genes - and therefore we have a stone age phenotype - or that we need stone age food because of all the resulting traits from those genes.
I am not aware of any research into the genome that proves this. I am not even sure how that would work. Until such a discovery is proven this idea is pure conjecture. A major barrier to a discovery proving this is the principle in genetics that genotype and phenotype are not the same thing. The argument that your genome predetermines complex systems of the body in a purely linear and predictable fashion is not a contemporary view of genetics. What you see here is a very nice statement of this fact. Even if one could argue there is indeed a Paleo genotype, it does not follow that we are locked in to a Paleo lifestyle. As I said, genotype and phenotype are terms normally applied to specific traits, so it is a stretch to even look at it this way. Nevertheless, this the claim of Paleo-logic. Our phenotype is supposed to be responsible for us being unable to properly digesting oats, for example, despite all the evidence to the contrary. I think this is a really tough argument to make based on genetics. The distinction between genotype and phenotype is yet another flaw in Paleologic that nullifies the idea before we even consider it on a practical level.
The case that we have some sort of Paleo diet phenotype is harder to make when it seems phenotypic variation is a key part of how populations achieve fitness. How could there be one ideal diet for everyone if variation in phenotype is built into the genome?
Read enough about evolutionary biology and you will find that although it is very fascinating research that has attracted some great minds, it is often quite speculative. Cordain is well within this speculative tradition with his Paleo diet, although his idea does not seem modern in its specificity and internal consistency, or rather lack thereof. Let's see where others beside Cordain have stumbled in overextending or corrupting ideas born from evolutionary theory.
The most obvious example is the eugenics movement. Here you see a respectable-looking academic journal published by the Eugenics Education Society in 1916.
Today we know that in addition to being morally revolting, eugenics was irredeemably flawed scientifically. I include this slide so you can see how readily accepted it was by the intellectuals of time.
By 1920 evolution had become a tool for constructing a variety of pat explanations for complex human behaviors. Despite growing evidence that it lacked scientific support, eugenics was too attractive an idea for some to abandon. Like the appeal to nature, fallacious appeals to genetics and evolution seem to strike a powerful chord in some people.
Of course, the worst abuses of the theory of evolution have been in regard to race and ethnicity. The racist invoking evolution always thinks he is the more evolved, even as he wallows in base emotions of tribalism and violence. For the Nazis, their embrace of a hateful ideology turned out to be maladaptive.
The violence of World War II led some to conclude that evolution made us in to inveterate killers. Cruelty and war were just in our nature.
This, like meat-eating, was argued to be the explanation for our big brains.
Social Darwinism, too, was a concept glibly used to justify all manner of ideologies. On this slide please notice the last couple sentences, which make clear how this type of thinking is useless as it is inherently vague and speculative. You've seen already that Paleologic suffers from this same problem of free interpretation. Paleo ends up just being a rhetorical device for self-validation.
Once again I'll throw up Gary Marcus's book cover. His book is about evolutionary psychology. This might be another example of the potential overstretching of the theory of evolution.
Not everyone is in agreement about the value of the conclusions drawn from it.
Here is another example of the speculations you'll find in evolutionary biology. This author proposes there may be an adaptive advantage to an additional random epigenetic element to the genome beyond the normal background mutation rate. He can't identify a molecular mechanism to explain this. I'm not sure I understand his idea, but what I take from this abstract is that evolutionary biology isn't quite ready yet to tell me what to eat.
He mentions the antagonist pleiotropy hypothesis regarding aging. Longevity is an issue worth contemplating in regard to the Paleo diet idea.
Normally, when we discuss nutrition it is understood that a healthy diet rewards us with longer life, or at least good health lasting longer into old age. After all, the Paleo diet is targeted at foods its promoters believe cause Western patterns of chronic disease that take years to develop and harm us.
That's why I found it strange that in his defense of his original 1985 paper about the Paleo diet concept, Paleo nutrition founder S Boyd Eaton seemed aware that post-reproductive lifespan is little effected by the pressures of natural selection.
Think about it. If evolution is based on the passing on of genes, once a new generation is born and able to carry on, what does it matter how much longer the parents live? If our genome isn't affected very much after reproduction, then from the diet's very beginning, future claims that it's a way of giving us a longer life were short-circuited. This wasn't his intent in this quote, as here he argues that contemporary humans are not adapted to so-called novel foods because we wouldn't pay a price for them until we have already passed on our genes. Unfortunately for him, he can't have it both ways. The longevity argument for Paleo therefore is off the table. And if it's off the table, of what practical use is the concept? This is another serious logical problem for the Paleo promoters.
I'll return to the antagonistic pleiotropy hypothesis of aging now. Antagonistic pleiotropy is an interesting, albeit speculative, idea that states that traits need not be all good or all bad. A trait can help your fitness for passing on genes, but it can also hurt you in some other way that may not relate to passing on genes. In evolution, the gene that improves fitness is the one that matters. It's an important idea for those who say there is an ideal diet in our genome somewhere. There really is no reason to think anything is particularly ideal in the genome. Our genes can work at cross-purposes to our desires in life.
Here I will return to one of the authors in the article Cordain cited in his attempt to find support for his view that nutrition is an immature science. As I said, I felt the article in question actually undermined his philosophy. Randolph Nesse seems to be more comfortable with the potential contradictions in our genes that result from our lack of design. If you pause to read this, first, you will see he recognizes some obvious limits to the genome's impact on health.
Next, you will see that he understands the primary importance of reproduction in evolution and the potential that creates to undermine our health. Paleo dieters, is it more important to live according to your imagined genetic requirements, or is it more important for you to have a long and healthy life? I opt for the latter, so I am more interested in the best objective science for this purpose.
I'm halfway through my thoughts on this idea of having a diet in your genome. See you in the next video!
Primitive Nutrition 8: A Diet in Your Genes? Part II
In the previous video I explained why it is highly unlikely there is a Paleo diet in our genome. I was just getting going on the topic of longevity.
Here is an example related to longevity of how the speculation found in evolutionary biology can go wrong or be misconstrued. Read this abstract and you might come away thinking that somehow humans have a longer post-reproductive life span than other primates because we are so well-adapted to eating meat. This sounds good for the Paleo diet idea, which is why you will see this article wherever people argue against vegetarian diets and for Paleo diets.
But hold on a moment! It turns out we don't age much differently than other primates after all.
Something else the Paleo promoters are likely to overlook is this comment by one of the authors of the study they like so much.
"Stanford said that modern-day humans 'tend to gorge ourselves with meat and fat. For example, our ancestors only ate bird eggs in the spring when they were available. Now we eat them year-round. They may have hunted one deer a season and eaten it over several months. We can go to the supermarket and buy as much meat as we want.'"
That doesn't sound like much of an endorsement of the Paleo diet, does it? Once again, speculation about evolution and diet doesn't assure us we will reach the same conclusions.
Lifespan involves interesting issues of antagonistic pleiotropy. Here is a paper on calorie restriction and aging. I want you to notice here that the author states that it is unlikely that genes conferring longer lifespan have been positively selected to do so. We may want long life, but natural selection probably hasn’t done much to help us with that.
This scientist is not convinced that calorie restriction leads to longer life in humans. We must admit that the evidence for it is lacking, as he says.
Still, it's interesting to consider. Here is an abstract about lifespan. If you read this, you could interpret it to mean that your genome is more tuned to fertility than longevity. The term somatic maintenance here refers to the turnover of cells not involved in reproduction.
Here this author refers to protein synthesis rather than somatic maintenance but I think the point is the same. Growth and development are said to be at odds with lifespan, and this is mediated by caloric restriction.
Here is the sort of counterintuitive result this tradeoff might produce, if it works just this way. Fewer calories, less body maintenance, but better reproduction. Once again, perfection in the genome is elusive. Our genes work at cross purposes. And once again, even if we grant the Paleo premise of a diet in our genes, the idea may not mean much when we try to figure out how to live a long and healthy life.
Here's another example to show you how our genome might not be the greatest guide for our diet choices. This is about the so-called Asian flush reaction. Asians are less able to metabolize alcohol due to a point mutation. It is believed that this was caused by the adoption of the drinking of hot tea in the East as a way to purify water. In the West, fermentation of liquids into alcohol was the preferred method of water purification so Europeans generally can now tolerate alcohol better than Asians. Does this mean alcohol is good for people of European descent? Not necessarily. You'd need to look at current scientific research into health outcomes to know that. No responsible scientist or health official is recommending we drink alcohol on the basis of conjecture about our genes.
It's hardly likely that alcohol could be considered unreservedly healthy and natural for us even if it is well-represented in our genome. Anything you consume that can inflict this collection of problems can hardly make a claim to have a place in an ideal diet for humans. I would think that minimally an ideal diet should not induce birth defects, for example. And yet, if you're of European decent, there alcohol genes are in your genome. What if there were some meat-adaptive gene in your genome? Why would you conclude from that, that meat is part of an ideal diet?
Dairy is in a similar situation, and this is one where the Paleo dieters and I might agree, although for different reasons. Cordain uses an argument based on it's supposed evolutionary discordance to discourage its consumption. Yet not everyone is lactose intolerant. Does that mean if you are lactose tolerant milk is engraved in your genes as a healthy food? Not so fast.
The adaptation for those who tolerate milk well is called lactase persistence. This is because lactase, the enzyme needed to digest lactose, the sugar in milk, is normally lost after weening because it is no longer needed. In a neotenous adaptation, the trait of the juvenile phase persists into adulthood because it confers some advantage. But does this mean it is healthier to eat butter and drink milk throughout life? Why would we jump to that conclusion?
After all, other mammals lose their lactase production. Are we fundamentally so different because of a few polymorphisms?
It gets even fuzzier when you see that lactase persistence has evolved differently in different populations. If we all have a stone age genome that prohibits milk drinking, then why did natural selection find two different paths to put it in the genomes of these populations? This isn't what you'd expect if our genes were designed.
Lactase persistence is a great example of how our genomes differ. The only way to decide whether or not to consume dairy is through real empirical research, not by channeling our inner caveman.
I'd like to now talk about the concept of epigenetic expression. Epigenetics basically refers to the role of environment in expressing your genes. This is important here because it means your genes are not your destiny. This is understood by most of the Paleo diet promoters, with Mark Sisson coming first to mind. Of course, he thinks his diet ideas induce epigenetic expression in a uniformly positive way that promotes his ideals of appearance and athletic fitness. But should it be so simple? Let's take a look at examples of the impact of epigenetic expression.
Let's return to Randolph Nesse for a really interesting example of the effect of epigenetics. Here he points out that a childhood spent in a hot climate will affect the number of sweat glands the child eventually has in adulthood.
Mothers exposed to nutritional insufficiency give birth to young who develop the typical disorders of Westen civilization much more easily. In my Waking to Realities section you will see how this is playing out in parts of the world undergoing rapid changes in their diets with the addition of more meat, fat, and refined carbohydrates.
Notice the use of the word "fitness" in the last sentence.
Once again, this is not the sort of fitness Mark Sisson talks about. It is fitness in it's true evolutionary meaning. In evolution, "fitness" does not mean you are athletic.
I like this story as an example of how fitness in evolution may mean quite the opposite of what the phrase "survival of the fittest" usually conjures. Here, among baboons, the behavior of the most aggressive, dominant males made them unfit for their environment, allowing for the passing on of the genes and culture of the subordinate males. The subordinate males were fitter within the context of their environment.
But I digress. Back to epigenetic expression.
Read The Protein Debate and you will see that T Colin Campbell discusses the importance of epigenetic influences. Here you can see that as far back as 1986 it was known that nutriton in utero could influence the health risks of a baby. This was all coming into focus shortly after Eaton's original Paleo paper. Paleo-logic states that the answers to our health needs lie in our stone age genome. Yet the genetic makeup of an individual was known long ago not to be the full story. Paleo should never have gotten off the ground.
Look up the effects of epigenetics on nutrition and you will likely find studies about the damage done by a high fat diet, the sort of diet Mark Sisson says is healthy. Not only does a high-fat diet induce epigenetic havoc in the individual who consumes it...
And not only does it affect the offspring of mothers who eat it...
It can affect offspring through a third generation.
Even fathers can pass the effects of their bad diets along to offspring. Would an heir to this sort of nutritional legacy be better off eating some imagined historic fatty diet built into his genome, just because that's what a fad diet promoter says? Or should such a person eat a diet that is best for improving their health given their natural tendencies?
The idea of a hunter gatherer genome is wrong in another big way. Long before we were hunter gatherers, we were and are primates. This matters. I'll show you why in the next video.
If you want to breathe new life into the tired old low carb idea, you're going to need a fresh way to scare people away from carbs. The unique innovation that Paleo brings to the low carb business is the claim that grains and beans were first eaten too recently to be something our bodies can handle now.
In Paleo-speak, these foods are evolutionarily novel. I think this view is composed of three assumptions. The first is that these foods were new for humans 10,000 years ago. The second assumption is that some major adaptations to these foods were necessary. The third is that 10,000 years wouldn't have allowed enough time for these adaptations to become established in our population. If we grant that a typical human generation was around 20 years, then 10,000 years makes for 500 generations.
To address the first assumption, we’ll need to fact check their history. Here is evidence of cereals being consumed 19,000 years ago. That amounts to 950 generations.
Here is evidence going back 23,000 years. That's 1150 generations.
And here is evidence going back 30,000 years. These authors call grain use commonplace and widespread across Europe. Now we're up to 1500 generations.
There is even some evidence that grains were consumed as long ago as 100,000 years. Now we're up to 5000 generations. So much for that first assumption. The second, that adaptations to beans and legumes were necessary, I will address in just a moment.
Let's skip to the third assumption, the one saying 500 generations wouldn't have been enough for any important adaptations to become established, if we pretend for the moment that that's the right number. What evidence is there for that? Here we see that salmon can undergo reproductive speciation in fewer than 13 generations.
Here are lizards that developed a completely new gut structure that allowed better digestion of a vegetarian diet in only decades.
Here are a few other examples of quick evolution in animals.
What about in humans? Here you see that Tibetans have evolved a capacity to thrive at high altitudes in only 3000 years.
Native Americans have an adaptation to heat stress that needed as few as 12,000 years to develop, which is in the ballpark.
To scientists not invested in the Paleo diet idea, an insistence that humans have not evolved much since the Paleolithic is not an easy sell. These authors argue that the speed of evolution in humans has been quickened by the introduction of agriculture.
Human cultural change has subjected up to 10% of our genes to positive selection within the last 10,000 to 20,000 years.
The famous Paleoanthropologist John Hawks sees a recent quickening of evolution as well. He says lactase persistence, which allows some people to tolerate milk in adulthood, occurred in less than 5000 years.
I think the Paleo people are under the misapprehension that if blunt natural selection mechanisms have been less strong since civilization began, that somehow means we are not evolving. Actually, for evolution to happen, there only needs to be different traits with different effects on fitness. If a trait is advantageous, it should spread through a population faster than a trait that is not.
The concept of fitness seems to confuse Mark Sisson. Somehow he thinks humans were not subject to positive selection after the agricultural revolution. I'm not sure where he gets this idea, and I'd be interested to know who the many researchers are who say we are genetically identical to what he calls our primal ancestors, whatever primal means.
This is some of the best material I can find to support Sisson's claim that, as he says, "evolution essentially ground to a halt." The gist of this article is that maybe evolution has slowed down but it is hard to tell. I haven't seen any scholar outside of Paleo say anything about evolution grinding to halt.
In either case, this Paleo belief creates a paradox. If you believe it, then on the one hand, the Neolithic suddenly brought an easy life with no struggle to survive. Evolution halted.
But on the other, human health was stressed in new and devastating ways by bad nutrition. Should we imagine these nutrition problems did not create selection pressures? And should we avoid grains because of their troubles?
Paleo thinkers tell us people got shorter and less healthy when they started farming. They base this on the fact that human remains from back then show shorter stature and signs of nutritional stress. Not everyone is in agreement about this, but let's just concede this point.
So let's think about this paradox. Whether it was good for them or not, these people did eat grains. When a Paleo promoter says these grains were really bad for them, that means they should have been a force of purifying selection. The worse these foods were for them, the better we should be adapted to them today. Or, looked at another way, if humans haven't adapted much to grains since then, that means they weren't such a big problem. This is part of my response to that second assumption, that adaptations to grains and beans were necessary. Either way, it doesn't help the Paleo idea. So can we tell which scenario actually happened? It's hard to say. Genetic research suggests humans have improved their ability to digest starches since the beginnings of agricultural. That means that long ago people could not digest these starches as well as we can today, so it was an important issue. We benefit from this fact today.
But there are more important reasons we see evidence of stress in the skeletons of people who lived through this period. The most obvious one is that they simply hadn't figured out agriculture yet. They didn't get things right immediately. The new agricultural economy created new social and economic stratification that lead to conflict and repression, and this affected health. Those are hardly purely nutritional problems.
Another factor is that people of this time had not yet developed cultivars that met human nutritional needs the way our crops do today. To give you a sense of the importance of this, here is a potential range in nutrient densities among varieties of one crop, wheat.
Carrots give us a good example of how the nutrient density of a crop has improved over time. Visit this page and you'll see carrots have an interesting history. Wild carrots didn't offer the nutrition of today's cultivated orange carrots.
There were also new stresses from infectious diseases, a byproduct of the greater population concentrations enabled by agriculture. Infectious diseases need dense populations to spread. Surely this source of stress affected their health and therefore their remains.
This source also raises another issue. People also hadn't figured out the need for complementary proteins in their crops. We shouldn't be surprised that populations trying to survive on a very few staples ran into problems.
Cultures throughout the world have independently come to combine crops to meet their protein needs. These practices needed time to become established.
It is highly likely your culture has these issues sorted out better than the first farmers did.
Possibly the worst generator of disease in humans since the Neolithic is zoonotic infection. These are diseases that jump from animal species into humans. The establishment of a sedentary way of life allowed for the domestication of animals for meat and milk. Zoonotic infections remain a wellspring of pathogens for humans today, from the consumption of bush meat that likely gave humans the HIV virus, to the recent swine flu scare that originated in factory farms.
Past exposure to these diseases has shaped our immune system.
Here's another factor. Iron deficiency has been observed in human remains from back then. Parasitic infection was a likely cause of some of this.
Since we are talking about a diet that is based on evolution, we can look to Darwin himself for further insights into the challenges of those days. He understood the importance of population density. Populations can't multiply indefinitely. Eventually they are limited by the carrying capacity of their environment. That carrying capacity is dynamic. At some point a population will be severely stressed. People back then would have faced blight or drought with only weak coping strategies. They also would not have established robust trading systems to buffer them in times of shortages. Surely this accounts for some the hardships represented in their remains.
One mechanism that would have reduced population density, and therefore disease, for the stone agers was their extremely high levels of violence. Paleo promoters don't usually mention this side benefit to Stone Age culture.
The violent life of the hunter gatherers might have contributed to selection pressures for body size. It was more of an advantage to be bigger and stronger in a violent world. Once agriculture became established and the world became a bit more civilized, males might have become smaller.
Moreover, around the same time, hunter gatherers got smaller as well, in addition to many other mammals. This is a pretty damaging fact for the Paleo pushers. Changing climate might have caused this, rather than beans.
With all these far more parsimonious explanations, does it really make sense to blame grains and legumes for causing worse health for the first farmers? From my reading it seems Loren Cordain did not have a lot of company when he first made his case against cultivated crops. Give him some credit. At least his idea was evolutionarily novel.
In the next video, I will circle back to the idea that your genes require you to follow a Paleo diet.
Primitive Nutrition 4: Truthiness Paleo-Style, Part I
Here's an interesting phrase from Mark Sisson's book, The Primal Blueprint: What our genes truly crave." If you get comfortable with this sort of thinking, you can give practically anything you want an evolutionary justification. You could say, "my genes are hungry," or "adultery is in my genes". It's sort of a Paleo-logic version of "listening to your heart" or even obeying the voices in your head. Do you think I'm being unfair to Sisson?
Then you haven't met Grok. Grok is a handy rhetorical tool for him. Will fruit make me fat? Should I consume most of my calories from meat? Well don't worry about sorting through all that science, and certainly don't listen to expert panel recommendations on nutrition. Why assume they know what they're talking about? Just consult Sisson's imaginary caveman.
Why listen to a guy like this? All that research and study has probably just confused him.
You're better off imagining what this guy would have done. He may have smelled terrible and made lousy conversation, but he probably had six-pack abs. You know he loved going shirtless. Imagining what a stone ager would do is super easy, and it just feels right, doesn't it? Grok is the Paleo-logic symbol of truthiness.
This is how the Paleo world justifies its beliefs. See the last phrase? Our crusty imaginary friend would certainly be tipping his hat to us as we alternate gorging on meat with intermittent fasting. You just know he'd have charming mannerisms like that. Grok would probably be just be a great all-round dude, you know?
Of course, the ladies would have loved him. Most women these days would melt for a guy who could bring down a woolly mammoth. You can signal you are that guy by taking Sisson's advice and grunting and growling at the gym. The gym is the right place to play out your Paleo fantasies of tearing apart giant prehistoric beasts. If anyone thinks you're being uncivilized, that's their problem. As Sisson says, "If people are offended, they shouldn't be in a gym." You'll be feeling your primal best, and the ladies will be sure to notice!
Sisson does have a knack for connecting with adolescent boys of all ages.
Unfortunately, channeling one's inner barbarian doesn't seem to help the Paleo promoters agree on some basic nutrition issues. On one hand you have modern day Paleo radiologist Kurt Harris arguing plant compounds are not essential. This is worth hitting pause to read. He seems to be creating a bit of a straw man, implying that someone out there says there is a single phytochemical that is indispensable to human health. I have never heard such an argument put forth, but just in case someone does, Dr Harris is all over it. However, I'm not sure he has really addressed whether phytochemicals in edible plants are good for us.
"Fruits and vegetables hit cancer with a one-two punch: They're excellent sources of antioxidant vitamins and minerals... and they also contain a variety of special substances called 'phytochemicals,' nutrients found in foods that are lethal to cancer."
On the other hand, Loren Cordain believes phytochemicals are worth eating if you want to reduce your risk of cancer. Did he ask his genome what it craved to figure this out? Both of these guys are on the cutting edge of that big paradigm shift to Paleo. Why don't they agree on something so basic then? This isn't the only example of Paleo-logic leading to very different conclusions.
From the beginning, the Paleo diet idea was sold as something really different from low carb, even though it was low carb. Those other low carb diets were hazardous. This low carb was better because it was closer to the recommendations of major health institutions like the American Cancer Society. Well, if these institutions are the ultimate source of validation for a diet, why then do we need the Paleo idea? Why not just see what the American Cancer Society says directly?
Let's see, fruits, vegetables, cutting out modern abominations like fries, doughnuts and sodas. Hey, they are doing Paleo!
Except they also say you should eat whole grains and limit red meat. Man, it's too bad they messed that part up, isn't it? I guess they never consulted Grok.
This nutritional plan is totally unlike those irresponsible, low-carbohydrate, high-fat, fad diets that allow unlimited consumption of artery-clogging cheeses, bacon, butter, and fatty meats.
Here's Loren Cordain calling all the other low carb diets irresponsible. They would have to be. There is only one original biologically appropriate diet for all humans and he's trademarked the name of it.
You see, the Paleo Diet is indeed low carb. But it's not like them. It has a big idea. Those other low carb diets on the other hand can be lethal.
But wait a moment! The Paleo diet is modeled on hunter gatherer diets. What did hunter gatherers actually eat? Were they staying away from lethal fats back in 1922, long before industrialized foods might have entered their diets?
It seems they really liked the parts that were most loaded with saturated fat. It even looks like Apache Indians didn't mind parting with the lean meat Cordain says is so healthy.
By the way, just imagine eating fresh hot raw bloody bison liver by the handful. Yikes!
Going back much further you can see that hominids may have prioritized the fat in a carcass, too. Some Stone Age diet proponents use information like this to argue for eating lots of animal fat. In an unforgiving ice age that might make sense, right? They could use those calories to add body fat.
Loren Cordain does seem just a bit off when he says Paleo man ate a diet that would have burned off his fat reserves. Isn't his idea of fighting a battle of the bulge with his diet a little more modern day vanity rather than evolutionary science? Ignoring for now the question of whether or not eating a lot of protein will make your fat simply melt away, what survival advantage would a Paleolithic human have found in being skinny? Would a fast metabolism have been an asset in the struggle to survive?
I’m just getting started with showing you how Paleologic has led to some seriously conflicting beliefs. There is more ahead in Part II.
Primitive Nutrition 5: Truthiness Paleo-Style, Part II
Loren Cordain is a believer in low cholesterol. He came to this opinion because hunter gatherers seem to have low cholesterol. There’s a little more to that story that I’ll reveal later, but at least he is giving a responsible opinion. He deserves credit for that.
You might think Cordain's views on cholesterol and saturated fat would make him a target for the high-fat Paleo promoters. Not necessarily. For some committed low carbers, promotional back scratching is more important than presenting a consistent message. Cordain has chosen to have Michael Eades provide the endorsement on his cover. This is a little awkward, as Cordain thinks you were designed to go low carb the lean meat way, while Eades goes so far as to say the state of ketosis, in which your basic metabolism changes dramatically on an extreme high fat diet, is the natural human metabolism.
Dr Eades recently went far out on a limb in support of eating lots of saturated fat.
Have a look at this quote. Remember, Cordain has called saturated fats lethal. Eades, on the other hand, will think you're a wuss if when you go low carb you don't add extra fat to your already fatty meat. For God's sake, he says, don't listen to your body. You want the fat dripping down your arms.
Eades is an ardent defender of saturated fat. In 2009 ABC news did a little experiment to show what happens in your blood after a high fat, high calorie meal.
Here you see two different blood samples after they have separated into their plasma and red blood cell layers. Guess which one came after the fatty, high calorie meal. The segment left the impression that it was the fat in the meal that caused this.
Eades didn't appreciate this piece and wrote a scathing blog post to argue it was the carbohydrate in the meal that was to blame for that cloudiness.
This is an excerpt to show you his reasoning if you care.
That cloudiness after a meal is called postprandial lipemia. Postprandial simply means after a meal. Lipemia has been associated with heart disease and diabetes, so he doesn't want you thinking it comes with high-fat diets. So do carbs cause lipemia?
In normal humans, pure carbohydrate, in the form of glucose, lowers postprandial lipemia in a dose-dependent manner.
In contrast, here is a description of the process of how dietary fat causes lipemia.
In a controlled study saturated fat in particular was shown to increase these fats in the blood. Animal studies have shown the same thing. Even in diabetic individuals, fat was shown to increase insulin and fatty acids.
Here is a study that directly links high fat meals in healthy humans to fat in the blood and its ill effects. A low fat meal had no such effects.
ABC News heard the complaints of Eades and others, however, so they repeated the test with a lower fat meal. As you might expect, a lower fat, lower calorie meal produced much less fatty results.
“But to unequivocally say that saturated fats do not cause atherosclerosis, is sheer folly. “ Loren Cordain
“It might be (In fact I think it is) that a diet high in saturated fat protects against atherosclerosis.” Kurt Harris
“In fact, the evidence is that saturated fats are harmless, if not beneficial, and that trying to avoid them is as likely as not to be as detrimental.” Gary Taubes
“... saturated fats do not contribute to heart disease and in fact actually protect us against this and many other diseases.” Sally Fallon
Here are a few quotes to give you an idea how all over the map opinions are about fat among people who use Paleo-style truthiness to make diet recommendations. Loren Cordain, who has published many journal articles to bring intellectual respectability to his ideas, is smart to stake out the more conventional position. These differences between low carbers are often papered over in the low carb community.
I think it's worthwhile to see exactly how far out in left field Paleo-logic can take you. Here is an actual quote from Paleo promoter and radiologist Kurt Harris.
"I don't think any person on the planet needs to have any of their lipoproteins or cholesterol tested ever. I think it's all worse than useless because, what happens is - and I get these emails all the time - you know, eating Paleo, feeling great, blood pressure decreased, no longer on medication, no longer have diabetes... bench press 250, and then they say, but, but, my total cholesterol is now 290 or 300 ...
My answer to that is, well, you were doing fine until you got your cholesterol measured."
You probably know this is not an opinion shared by most doctors. To show how bad this advice is, let's consider people who have an inherited tendency toward high cholesterol.
People with inherited high cholesterol, called familial hypercholesterolemia, have many times the risk of dying from heart disease as other people.
The mean age of death in hypercholesterolemic men was only 54 in this study. Heart disease can be detectable as early as 17 in these people.
Sudden cardiac death is the leading cause of death under 65. In this study of people at autopsy, coronary artery disease was the most common cause of sudden cardiac death between ages 20 and 40 as well. Blood cholesterol was shown to be a major risk factor.
Bear in mind, you can have high cholesterol and heart disease while being totally asymptomatic. This is especially true for women.
And it is possible to have a fatal heart attack as the first symptom of heart disease, even if you are young.
The untimely death of Tim Russert raised awareness of this issue a few years ago. Here you see that like in him, 40-60% of the time sudden death is the first sign of a problem. In light of these facts, it's hard to believe an MD would say it's not important to know if you have familial hypercholesterolemia. But I guess a blood test isn't very Paleo.
Now before you think that Loren Cordain's view is the right one, let's look at his clarified position on saturated fat. Yes, it causes a buildup of plaque in the arteries, he says. That won't be what kills you, though. In his Paleo-logic, there is no problem with an ever increasing amount of cholesterol-filled, calcified plaque in your arteries. Your arteries will just keep expanding to compensate for that. But eat some bread, and your cholesterol-laden plaque can turn lethal as it breaks free and kills you. In his mind carbs cause inflammation and that's the problem. I'll look at this idea in another video, but for now, realize that even for the most responsible Paleo promoter, you need to be comfortable with a diet that causes a slow and steady buildup of plaque in your arteries. That isn't my idea good heart health.
Cordain is right in a sense. To have a heart attack you need plaque to break loose, and this can happen even in people who don't have advanced atherosclerosis. This doesn't change the fact that some plaque must be there to break loose.
Cordain and other low carbers want you to think they know why plaque breaks apart but really they are just speculating. Plaque rupture doesn't lend itself very easily to study in humans.
And there are no good animal models for it and there may never be. I don't think Cordain's conjecture is enough to make the build-up of atherosclerotic plaque acceptable. I'll eat foods that are known to promote heart health instead, thank you very much.
One of the sillier examples of the use of Paleo-logic to justify personal preferences and idiosyncrasies comes from the economist Arthur De Vany, shown in video 1. He objects to distance running using Paleologic. This blogger does an excellent job of responding to his ill-considered belief. It's worth a read.
Actually, this evolutionary biologist thinks the capacity for distance running was a key development in human evolution. Of course, he is an avid distance runner and De Vany is not, which probably explains why they wound up having opposite beliefs about this.
One can easily use Paleologic to argue against De Vany and in favor of distance running. After all, bipedal efficiency, thermal regulation through sweating, and the hunter gatherer practice of persistence hunting could make a typical Paleo-type argument in the other direction. Which truthy argument do you prefer?
Here's my point in this video: If the Paleo idea means such different things to different people, it's not a very useful idea. We'd be better off without it distracting us from the real nutrition science.
Paleo promoters tell us certain foods are bad for us because they haven't been around long enough for us to handle them very well. In the next video, you'll see why this is nonsense.
It is my opinion that at its root the Paleo diet idea is just another version of a fallacy called the appeal to nature. The Fallacy Files website shows us how this fallacy can appear in discussions of diet and lifestyle. It also makes the point that something is not necessarily better just because it is considered natural.
Many primitive cultures have practiced cannibalism.
There exists archaeological evidence of our hominid ancestors practicing cannibalism nutritionally. So is cannibalism natural? Does our genome require us to eat each other? I certainly hope not.
I'm a vegan who eats a lot of fruit so I think it's only fair for me to give you an example of this fallacy in some other vegans who also eat a lot of fruit. This story is about a fruitarian couple who were put on trial for neglect in the death of their daughter. These people in all likelihood believed they were putting into practice the perfect natural diet. If you are a Paleo dieter, I'll bet you have no trouble seeing how that belief blinded them to reality as their daughter withered. They had plenty of warning signs, but they had this idea stuck in their heads so they missed them. Ideas like this can be powerful.
The Paleo diet is often defined in absolutist terms that might resemble the rhetoric of a radical fruitarian. It's "the optimum diet for the human animal." How convenient! It's optimum by definition! If accepted literally, this rigid belief has the potential to blind someone to any flaws of the diet, just as the fruitarian couple was blinded. The Paleo writings I've seen are laced with this sort of dogmatism.
In this excerpt from The Paleo Diet, Loren Cordain uses some mind-closing absolutist language as he states that his diet is the one and only diet that ideally fits every person. It is unusual to hear someone who calls himself a scientist speak in such a dogmatic way about an opinion that is not widely shared by other scientists. It's also unusual to see a scientist so strongly embrace the appeal to nature fallacy.
Scientists rarely engage in absolutist language when they propose new ideas because they know there is always the possibility new data will force them to reconsider.
They know this is an inherent strength of scientific reasoning, as all ideas are open to challenge by better ideas.
When Cordain says there is a one and only diet ideally suited for all humans, a diet fixed in a time and place in the distant past, he is essentially saying that in a practical sense, there is no possibility of progress or improvement in nutrition. This is quite an extraordinary claim before we even consider the substance of it.
The use of absolutist rhetoric is avoided by scientists for obvious reasons. Take for example his statement that 500 generations ago every human on Earth ate the Paleo way. 500 generations is roughly 10,000 years. All one would have to do to undermine this statement would be to find just one example proving people ate from his banned foods list before that.
Here you see that in fact humans were eating quite a lot of legumes far earlier than that, between 65 and 48 thousand years ago. What does that do to Cordain's thesis? Should we now say instead that legumes are required by our hunter gatherer genome? But I thought the Paleo diet as described in his book was the one and only ideal human diet!
This is why scholars who wish to be taken seriously do not make arguments that can be nullified with only one data point.
He also uses the "design" word, as in you were designed to eat this way. Here we have a scientist whose whole argument is based on evolution who is seemingly unaware of the teleological argument, perhaps the first and most enduring argument against the idea of evolution since it was first proposed by Darwin and Wallace.
Of course, Cordain is not saying a supernatural creator designed man. He is using the less loaded term "nature," instead. Either way, anyone familiar with evolution should know that just because something in nature appears to be designed, that does not mean it was designed.
Here he veers more recklessly into this fallacy. Humans were meant to be meat eaters? Who meant that for humans? Nature? What does that mean? What else does nature mean for us? And how can Loren Cordain tell? Are we also meant to have parasitic infections? This may seem like a quibble but this language is utterly alien to those who study evolution. So why does he talk like this? He needs an absolutist view to make his diet ideas work. He needs you to feel that you have no choice but to buy in on Paleo all the way. The choice has been taken out of your hands. You simply were meant to eat meat and avoid grains and that's that. It is etched indelibly in your genome, so there is no need for further questions.
The idea that we are meant to be something or not, or that we are designed in any sense, implies a creator. This is a religious argument that is not sustainable in a scientific context. It assumes there can be perfection in nature, which I will show you later is a troublesome concept.
To set Cordain straight I will invoke an expert no less than Richard Dawkins, who makes clear any appearance of design in biology is an illusion.
Dr Cordain, there is no design in evolution.
I'm going to focus now on this online publication called The Protein Debate. In it, Loren Cordain and T Colin Campbell of The China Study fame go head to head on the topic of human protein requirements. The protein discussion is not as interesting as the statements of philosophy from each man. Cordain lays out his beliefs in a way that I find highly revealing of the sort of thinking that led to the Paleo diet.
Read blog posts like Robb Wolf's about The Protein Debate and you will see that the Paleo dieters think Cordain bested Campbell in decisive fashion. I have not seen any Paleo dieters address the concerns I will raise here, which I take to mean they are in at least general agreement with him. This should be no surprise because without these beliefs, the diet philosophy falls apart. Wolf makes it clear once again that I have apparently taken on a real challenge in criticizing the Paleo idea, putting me in the same category as flat earthers in his estimation. He likes Cordain's statements in the debate enough to do a big copy and paste job of them, as you see to the right. Can you blame him? Remember, Cordain is one of the world's most renowned scientists.
To the left you see a cartoon of Wolf, presumably finding eternal truths about the evils of evolutionarily novel foods in his beaker. These guys are super sciency. Wish me luck!
I'll start my look at The Protein Debate here, a few paragraphs into Cordain's first essay. Cordain seeks to draw a contrast between nutrition science and other sciences by portraying it as immature. So immediately, the exercise physiologist and primitive diet researcher has condescended to an entire field of scientific inquiry.
In his second essay in The Protein Debate, Cordain further reveals his contempt for nutrition science, with multiple uses of the word "discoveries," which he sarcastically surrounds with quotes each time. He seems to think that if something discovered has always existed, the significance of its discovery is somehow lessened. It’s like he is saying, "So what if you guys discovered we need vitamin B12? If you understand the genome the way that I do, you don't need to bother discovering these various and sundry little nutrients." Once again, Cordain sees a field of science as a finished business. How unusual for a scientist to express this attitude toward scientific discovery!
If we return to the previous slide at the left, his first example of what he calls a well-developed discipline is cosmology, with its Big Bang. Do cosmologists have a similar view of, quote, "discoveries"?
Cosmology is a strange candidate to prove Cordain's point that a mature science needs a universal paradigm. He says in the paragraph to the right that without an overarching template, there is disagreement and confusion in a discipline, which he feels is a big problem. None of that in cosmology, right? If you were about to ask, yes, he later uses the phrase "unified theory."
And there it is. Cordain evidently thinks cosmology has a unified theory, while nutrition does not. That is a doozy, isn't it?
If you are unaware, there yet remains to be described a Grand Unified Theory, or a Theory of Everything, that would resolve the contradictions between quantum mechanics and general relativity, and in so doing explain the Big Bang. The lack of such an understanding has left some rather huge gaps in our knowledge of the cosmos.
For example, the ordinary matter we know and understand comprises less than 5% of the observable universe. All the rest is quite mysterious.
And it has been proposed that there may be multiple universes beyond the known universe. These are some pretty big blind spots in cosmology.
How did Cordain decide cosmology was a mature science with such enormous questions left unexplained? Would he dare call physics an immature science? Does he think astrophysicists are gratified or embarrassed when new discoveries are made? After all, their science is only trying to explain things that already exist.
In the paragraph on the right, Cordain says that nutrition has a chaos problem, with disagreement and confusion in the discipline. This is actually not the case. The world's major health institutions agree on most of their recommendations. Confusion mostly just happens at the bookstore and online due to fad diet promoters like him.
Here’s another strangely revealing quote by Cordain. He says, "When the data consistently do not support the hypothesis, it is inappropriate to manipulate and selectively use flawed data to continue to support the erroneous hypothesis." Then he oddly provides a reference for that statement. So researchers shouldn't cherry-pick or use bad data? Is that so controversial he needs to provide a citation? I think it's odder still what that footnote is. Notice it's a whole book. Does he think this is the one resource that, when read in its entirety, will convince people not to distort data? No. This reference tells us he is driving at something else. He thinks he has a big idea.
Here is the Wikipedia page for the book he has referenced, called The Structure of Scientific Revolutions. He has just taken us on a detour into the philosophy of science, reminding us of Thomas Kuhn's idea that science advances through periodic profound revolutions, or paradigm shifts.
Each revolution entirely replaces the last because they are in conflict and cannot be reconciled.
An example of this would be the Copernican Revolution, which placed the sun at the center of the solar system, rather than the earth. Because he chose this reference, Cordain does indeed seem to have a grandiose appraisal of his hypothesis.
It is worth pointing out here that Kuhn's ideas are hardly universally embraced.
I have to wonder, what is the old paradigm that the Cordain revolution would replace?
The USDA MyPlate graphic? I think Kuhn might have been underwhelmed by this revolution.
Stay with me for Part II of I, Copernicus. I have lots more on the Protein Debate just ahead.
Primitive Nutrition 3: I, Copernicus, Part II
Let's go back to look at another footnote, number 11 on the top right. Cordain is citing someone else's work to support his assertion that nutrition science is immature. Who else would say such a thing?
Here's the article he is citing. I'm not sure it supports his opinion about nutrition science or his Paleo Diet very well.
So does it say nutrition science remains immature? Not at all. Here you see the single appearance of the word nutrition in the article, but it's about how poor nutrition affects a fetus.
This article actually is a great argument against the design fallacy. It gives a litany of examples of health challenges arising from our lack of coherent design. As I have stated, the Paleo Diet concept is totally invested in the design fallacy, so this article is bad news for Cordain, whether he recognizes that or not.
Recall from his book his belief that there can be such a thing as an ideal diet for us. There can be only one. Our genome is that coherent.
This is echoed in the rhetoric of other Paleo promoters, like this podcast host. Who wouldn't want to believe his warm-and-fuzzy that humans are not broken by default? By implication, the belief seems to be that if only we eat and live like a stone ager, we will be happy and healthy and trouble-free. This is a childish belief. Mature adults are accepting of the imperfections in life.
The next time someone suggests that humans aren't naturally conflicted, incoherent, or somehow broken, remember the Online Mendelian Inheritance in Man database, where all the thousands of diseases of genetic origin are catalogued.
Or just listen to this song.
Perfection is a pretty elusive concept in science. The two nearest examples of perfection I can think of are merely shapes. Here are the balancing gyroscopic spheres in the satellite Gravity Probe B. These are the most perfect objects created by humans, as far as I am aware. They are not perfect spheres, but darn close.
The most perfect object I can think of in nature is the electron, which is indeed fantastically round.
Now contemplate the human genome, with its more than 3 billion base pairs. What chance is there it could be perfect, as in free of contradiction? Not much, folks. I’ll explain that further a bit later.
For now let me just offer this as an example of why perfection is such a difficult idea to pin down in nature. You can pause the video to read this classic case involving moths. As their environment changed, their different colors gave them different levels of fitness. The circumstances of all creatures change, not just moths. Evolution just has to produce results that are good enough to keep going.
Let's return to the Protein Debate. Cordain believes our dietary requirements are encoded in the genome in some specific and knowable way, so specific that you could capture it in a diet book.
Here is a paper Cordain published along with a cardiologist that makes explicit his belief that a hunter gatherer lifestyle is embedded in our genome.
For a different viewpoint, have a look at what T Colin Campbell says about nutrition in The Protein Debate. He rejects what he calls reductionism in nutrition. He is not interested in responding to all the individual studies of particular nutrients that Cordain cites. Instead, Campbell believes nutrition plays out in a complex biological system. I think he has a point.
Campbell likes a holistic approach to nutrition, which is not such a strange idea in other biological sciences.
This approach recognizes that the whole is more than the sum of the parts, and that complex interactions give rise to emergent properties.
The recognition of the existence of complex adaptive systems is not exclusive to biology, either.
This applies to the genome and to nutrition. Proteomics, or the study of all the proteins produced by genes, is a concept necessitated by the limitations of studying just the genome.
The proteome is much more complex and challenging to study than the genome.
It is understood that proteomics is highly relevant to nutrition research.
The proteome isn’t the only layer of complexity over and above the genome, however. Here to the left are more, including the transcriptome and the metabolome.
And they, too, are understood to add complexity to nutrition science.
Cordain is aware of all this. Here on his own site when asked whether his view of the genome as the sole determinant of our nutritional needs can be reconciled with nutrigenomics, he simply answers yes. That's it. He then just regurgitates the programmed Paleo article of faith about how our nutritional needs are in our caveman genome, and that means no grains. I don't feel enlightened at all by this answer.
Just for fun, let's ask how without a big idea like Paleo or veganism to simplify things we could use nutrigenomics to create concrete, science-based, personalized nutritional recommendations based on the subtleties of the genome and everything else. Pause the video and read this slide if you like. You’ll see that reaching these goals would be a monumental task.
You see, in their own ways, Campbell and Cordain are both rejecting this approach. They are both rejecting reductionsim in favor of big themes. Cordain just wants to have it both ways. He cites lots and lots of studies, but he also ignores far more studies, the studies that don’t help his agenda. Actually, Campbell’s views are better supported by the literature than Cordain’s are. That will be made clear throughout the Primitive Nutrition Series.
Cordain wants a big unifying principle to harmonize every finding of nutrition science. This is an unreasonable expectation.
Scholars outside the bio sciences sometimes wonder why the workings of life don't adhere to rigid universal laws. The answer, Cordain should know, is found in evolution itself, which is inherently random and undirected.
Cordain's expectation that the body’s metabolic processes should be easily simplified does not square well with a modern understanding of biological systems. It is understood that homeostasis relies on probabilistic feedback loops. Short-term observational studies or studies which focus on one or two outcomes can’t demonstrate the full consequences of dietary patterns, yet short-term studies are all that low-carbers like Cordain have to offer.
I'll throw this up here to remind us of the scientific method. An honest application of Cordain's requirement that all data be entirely clear and coherent, without any appearance of cherry-picking, would place all nutrition science trapped in a repeating loop of constructing and revising hypotheses without ever reaching conclusions, as there is always some little study out there that contradicts the preponderance of the evidence. This is not only a result of the complex interactions our bodies have with food. It is also a result of variations in study designs and, naturally, the biases of the researchers.
Let's ask whether Cordain's idea of an evolution-based diet as a unifying theory of nutrition even meets the basic definition of a theory.
In these definitions a theory must offer a comprehensive, well-substantiated explanation of some aspect of the natural world. It must be so powerful it not only accounts for everything already known, it must have predictive value for future discoveries.
It also should be falsifiable. If it isn’t, it really isn't scientific. If you pause this to read the bottom section, you'll notice the distinction made between a hypothesis and a theory. At best, the Paleo nutrition idea is a just a hypothesis.
Falsifiability is a big problem for this hypothesis. Let me show you why. One of the arguments put forth by its promoters is that the diet is, in the course of digestion, net base-, as opposed to net acid-, producing. In contradicting that, this paper established what should have been obvious: that a diet that relies so heavily on meat will be net-acid producing. Hypothesis falsified, right, Dr Cordain? Time for a retraction?
Nope. Cordain simply responded that this paper somehow served to advance the original Paleo idea. Rather than admit he just got nailed, he tries to co-opt the paper's critique, and he hopes you won't notice. I included a few additional sentences that reveal his disingenuousness if you want to pause and read this. Standard Paleo blather is regurgitated, of course. An assertion is made that health problems developed as a result of the inability of evolution to keep pace with new foods. There is once again a reference to a whole book. Then you see he conjures imaginary unbiased observers who - naturally - would agree with him.
This is a handy technique, isn't it? I could say unbiased observers would say Loren Cordain is just a slippery diet salesman but I won't because that's would sound like I'm quoting an imaginary friend. His point is people are unhealthy because they followed the dietary advice of the major health institutions. Now does that ring true to you? How many obese people do you know who are religiously following the DASH diet or the USDA food pyramid?
At the end he shakes off the blow he just took from that paper and instead reasserts the need for a paradigm shift in nutrition, which he says will require mental agility. I'll give Cordain that. He is certainly mentally agile.
Pseudoscientists start with an idea they want to prove, and then backfill supporting data as it suits them. We have just seen one way the Paleo fad evades falsifiability. I will show you more later. It is my contention that Paleo diet promoters consistently fall into this pseudoscience pattern.
Let's now consider the idea of predictive power, a component of the definition of a proper theory. What does a Paleo diet theory predict, exactly? How would this be testable? If you think the answer is seen in the health of observed hunter gatherers, I will show you how it fails that test in another section. If the answer is the archaeological evidence of the diets of real ancient Paleolithic hunter gatherers, that is not truly testable. I’ll cover that as well. If you think this idea has been proven in controlled trials I will show you that their studies fall far short of any standard of proof. In fact, I will show you that there is much better evidence supporting diets that oppose the Paleo Diet.
Make no mistake, I am not questioning the fact of evolution. The theory of evolution has indeed been verified both experimentally and through prediction. Here are examples of the fossil finds and genetic evidence that it was used successfully to predict. Visit this site and you will find no references to the predicted benefits of cutting out lentils or eating lots of meat.
This is a nice explanation of how predictions work, and how they don't, within evolutionary theory. One cannot predict with any accuracy how the evolution of organisms will play out.
So what does this all add up to? Before we even get into the specifics of the Paleo diet, we can see its principal promoter expects to transform a field of science which he doesn't seem to understand, and we see he holds the ideas of others to standards his own ideas could never meet.
Next, I'll show you that the Paleo diet idea is so vague, it's practically useless.
Share Article →