The beef I have with The Paleo Diet

I’ve heard a lot about “The Paleo Diet” lately and every time a popular news source (say NPR or ABC or Fox News or New York Times) does a piece, I cringe a little bit. For those of you who have never heard of the Paleo Diet (from Wikipedia):

The paleolithic diet…is a modern nutritional plan based on the presumed ancient diet of wild plants and animals that various hominid species habitually consumed during the Paleolithic era—a period of about 2.5 million years duration that ended around 10,000 years ago with the development of agriculture.

So that’s the basic idea – people restricting their diet to things that we ate before modern agriculture. I don’t really have a problem with the diet, per se – removing highly processed foods and increasing your activity level is a good idea for almost anyone. But the rationale that always accompanies the diet – that’s where the cringe comes in.
The rationale goes like this (again from Wikipedia):

Paleolithic nutrition is based on the premise that modern humans are genetically adapted to the diet of their Paleolithic ancestors and that human genetics have scarcely changed since the dawn of agriculture, and therefore that an ideal diet for human health and well-being is one that resembles this ancestral diet.

I can break this rationale down into three assumptions/statements:
1. Evolution acts to optimize health.
2. Evolution adapted us to eat a specific diet.
3. Therefore, today, we should eat that diet to optimize our health.

As an evolutionary biologist, I think there are logical and scientific flaws to each of these statements.

1. Evolution acts to optimize health.
FALSE. Evolution acts to optimize fitness (the scientific term for how many babies you leave behind), not health (how physically fit and free from disease we are). The line that connects the modern idea of individual health and evolutionary fitness is not necessarily a straight one. For example, many of the “diseases of affluence” that the Paleo Diet aims to alleviate (obesity, heart disease and adult-onset diabetes) have not been shown to actually and negatively affect human fitness. In fact, there is even some correlational evidence that people we might currently describe as “less healthy” have more children and therefore might have higher fitness. Evolution doesn’t really care about health past the point where you’re healthy enough to make a baby. And if our goal is to achieve a modern ideal of health, recreating the conditions to which our ancestors were putatively adapted may not help us get there.

2. Evolution adapted us to eat a specific diet. 
TRUISM/FALSE. The truism here is that evolution has adapted us to our diet. All living things are the product of evolution; Homo sapiens has evolved to be an omnivore. The Paleo Diet makes a far more specific claim, though: that there is a single, specific diet to which we adapted in the past and that we have not since evolved. First, this assumes that all Paleolithic humans ate the same things in approximately the same proportions. This cannot be correct. Even on small geographic scales, the relative quantities of meat, fish, and vegetable matter available for human consumption change drastically. If I had to hunt/gather on the Louisiana coast for my dinner it would look totally different than if I were doing the same in northern Louisiana. Not to mention that one place would differ on a month-to-month basis. Seasonality and geography dictate what would be available to eat, not our evolution.

Second, this assumes that no evolution has occurred since the advent of agriculture. This is demonstrably false. One example of post-agricultural evolution is the human lactase gene, which breaks down lactose, the dominant sugar in milk. In ancestral humans this gene was turned off after infancy; those humans would have been “lactose-intolerant”. Most humans of European descent now have a mutation that keeps that gene turned on their entire lives. Not surprisingly, this gene spread throughout Europe at approximately the same time cattle were domesticated. There are other known examples of agricultural dietary adaptation, and doubtless more to be discovered. If we are going to use evolution to justify our dietary choices, why throw out the last 10,000 years of it?

3. Therefore, today, we should eat that diet to optimize our health.
HMMMM. Omnivory probably does optimize our health – I think a lot dieticians would recommend eating a variety of fruits, vegetables, grains and meat for an ideal diet. But the Paleo Diet has restrictions on which foods you can eat based on when they were introduced to the human diet AND what we know about them based on modern science (list of Paleo foods here & new link not requiring password here). For example, lean meats good, fatty meats bad. Paleolithic humans probably ate fatty meats every chance they got, don’t you think? Good fat was probably hard to come by in some places. We just think of fatty meat as “bad” because of cholesterol and whatnot – I’d go so far as to say evolution has trained us to love fatty meats, isn’t that why bacon tastes so good?

            

Here’s the other thing: basically anything you buy in a store probably wasn’t around a million years ago, regardless of how close it seems to being “natural”. Humans might have eaten wild pigs, but modern pigs are a different beast altogether. The same goes for apples or carrots or organic blueberries. Oddly enough, diet soda makes the “Foods to be eaten in moderation” category but “Dairy” is to be avoided entirely. What evolutionary sense does that make?

In summary, humans are certainly a product of their evolutionary history, but ALL of it, not a restricted subset of it. That history can give us great insight into why we are the way we are, and it might be a great way to generate hypotheses about which foods we should eat and in which proportions in order to be healthy. There is, however, a lot of uncertainty about what ancient humans actually ate, and whether that food made them healthy. Furthermore, evolutionary reasoning may explain what things we observe today, but it cannot be used to tell us what we ought to do. That is the realm of modern scientific evidence, not evolutionary first principles.

Now if you’ll excuse me, I believe someone mentioned bacon?

PS – Noah Reid contributed greatly to this post.

PPS - The wikipedia page for the Paleo Diet has a lot of information with a bunch of citations to primary literature on many aspects of the diet; check it out if you’re interested in what the experts have to say.

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33 comments on “The beef I have with The Paleo Diet

  1. rgibbo3 says:

    Great post. Being a current practitioner of fitness, I am wondering about one of your statements about the fitness of unfitness. Fitness does not end at birth right? I want my offspring to have offspring and that takes a little more time, a little more than a decade. I hypothesize that post F1 health affects fitness.

    And another thing. I have wicked lactose intolerance. Can I get student loan forgiveness or preference points for government jobs? That would be helpful right about now.

    • noahmattoon says:

      I would agree that the definition of fitness in the post is simplistic and that it is a totally reasonable hypothesis that parental health post-birth may play a role in offspring survival, but I don’t necessarily think that being free of “diseases of civilization”, the primary focus of the paleo diet, which seem largely to effect quality of life and longevity, are obviously linked to lower fitness.

      Also, I think the broader point is pretty solid, that evolution acts to optimize fitness, not health, and that those outcomes are not always in line. I think it’s also interesting to consider that an implied result of achieving the goal of “health” is longevity. Given that the processes of aging and senescence are certainly products of selection, I think many people might be interested in finding a diet and exercise regime that might allow us to escape our evolved physiological and developmental program, rather than enhance it.

    • Hird says:

      you’re right, fitness doesn’t end at birth. we definitely glossed over details in the post, but the main points still stand, i think (since non-paleo eating people don’t just keel over as soon as they’ve reproduced). i didn’t want the post to be too long.
      maybe you could get some loan forgiveness if you identify a person with the power to do that then chug some milk before having a closed-door meeting with them. let me know how that works out.

  2. OMG would you rather be fit or healthy? Are you healthy just because you can run and lift. Why is he defining fitness as how much a woman can procreate? Does that mean men are not fit? I don’t think obesity, heart disease or adult-onset diabetes are diseases of affluence….have you been to Wall-Mart or a State Fair? Paleo does not accommodate drinking soda! When people switch to a Paleo diet, the diet refers to limiting inflammatory foods, like dairy because it’s not the same dairy, meat or plants that are ancestors ate. Paleo encourages grass-fed, heritage seed and non-GMO. Do you think people are going to reproduce in a few generations after eating soy, wheat and diary from grain fed animals and GMO crops. I eat Paleo and am healthier for it. The people I know who eat Paleo have increased heath and fitness. I don’t see a lot of encouragement when I see what people have evolved into eating the foods that are not Paleo.

    • Hird says:

      Hi Christy – First, I’m glad you’re eating a diet that makes you feel healthy. Like I said in the post, I don’t have any issue with the diet itself. Eliminating dairy and wheat might do some people a lot of good. The post is about how the rationale behind the diet, that we are genetically adapted to a specific diet that Paleomen ate and we must adhere to that diet, not because simulating it makes you feel healthier, but because we are evolved to. “Experts” are making evolutionary claims without any evidence that evolution has anything to do with it – I think it’s manipulative. It’s also disingenuous to say things like “grass-fed beef” is what Paleomen ate – any beef you buy has been selectively bred for many, many generations. Literally anything you can buy or grow in your yard isn’t what people ate one million years ago. And yes, I do think people will continue to reproduce, even if we ate nothing BUT soy, wheat and dairy. Because I think evolution has created amazing omnivores that can live literally anywhere on the planet, eat whatever they can get, and still procreate. That’s not to say that I think everyone should be doing nothing but eating and making babies; evolution has also given us big brains, and mine tells me – eat what is good for you and exercise.

      • pinandthrum says:

        I know I am late to the party but my god you have the patience of a Saint. Thank you for taking the time to work through the science with people and illustrating excellent points.

  3. seathechange says:

    Hi, I really liked your arguments and the way you broke it down. I’ve heard about the Paleo diet from some of my fitness obsessed friends, and though I didn’t agree with it I didn’t have the best reasons (especially being a vegetarian anyway). Now I can show them reason and logic and science as to why the idea is a bit… Skewy. Especially because I prefer modern friends to cavemen…

  4. Well…I’ve heard that a “paleo” diet consisted of eating the internal organs of animals…
    Can’t really imagine how modern humans would go about doing that…

  5. 1. The laymans term for fitness and the biologists’ term for fitness are different. Yes, evolution-wise fitness refers to the ability to produce offspring, but the majority of the public doesn’t define it like this. It does increase an individuals health. This is the purpose of the diet. So your first “debunk” is an argument of semantics.

    2. Some populations can process lactose, a LOT of populations still cannot. You also never bring up gluten. I find this interesting because you talk about all the mutations we have yet to discover how humans have evolved after the agricultural revolution but you fail to mention the newer discovery of a HUGE part of the population that has discovered they cannot proces wheat, rye, or barley. Most of these people have lived in varying degrees of pain their whole life not knowing why.

    3. I am not sure where that list of paleo foods came from but as someone who is on the diet I select fatty meats over lean meats. I would agree this diet is not for everyone, but any biologist will tell you that there is no one thing that is the best for all humans (except perhaps respiration). I spent my early childhood eating cereal growing up, I assumed it was normal to eat cereal, get really ill, use the bathroom, and then feel better for a bit before you eat again. My whole life from childhood to my early thirties was dominated by making sure I was near a bathroom when I ate. I went to doctors, tried a varying degree of diets (including being a vegetarian for 2 years) and all doctors told me was that I had IBS.

    Two years ago my body just started getting violently ill to the point of having to spend 3-4 hours in the bathroom, I got a battery of tests and nothing was found…..until my friend said “have you been tested for a gluten allergy”, not a doctor mind you, my friend. I was tested, discovered I had a gluten intolerance. I went on the paleo diet and within 2 months I felt like I was reborn. For the first time in my life I was pain free, I slept perfectly ever night, my emotional state became extremely stable, and then after a few months the blood work began to come back.

    Eating a diet of mostly fatty meats, fish, leafy greens, and fruits my weight dropped 30 pounds, my bood pressure went from 150/90 to 110/70 and my cholesterol dropped from 280 to 83. Yes, you read that correctly, 83. The doctor refused to believe the results based on my diet and made me get another blood test. Same results.

    While the paleo diet may not be for everybody, there is definitely a group of humans who can greatly benefit from it.

    • Hird says:

      Howdy. I agree with you that a group of humans can definitely benefit from adhering to the Paleo Diet. I have two cousins, an aunt, a mother-in-law and a sister-in-law with Celiac’s disease – it’s very serious! Not to mention, I’ve been diagnosed with IBS and tested for gluten intolerance myself, so I understand what a big-ass bummer gastro problems can be. (And how amazing it can be when you find something that works for you!)
      But that is all beside the point: no one has tested the scientific claims about genetic adaptation and diet. “Genetic adaptation” is a big deal in the life sciences and it’s hard to demonstrate even under ideal laboratory conditions.
      As for your response to my first point, it’s not semantic, it’s the difference between science and story-telling. Evolution is a science and it does NOT act to optimize “health”. Certainly, “health” and “fitness” are correlated, but that’s the whole point. You can’t just claim that “Evolution knows best” when it comes to our “health” because you’re then talking about apples and oranges. Evolution acts on “fitness”, diet practitioners care about “health”.

      • For full disclosure I am an evolutionary biologist who left research to become a high school science teacher. I am very well aware of the biological side of this.

        However I am also very aware of the publics ignorance toward science. When I worked for the smithsonian we actually had signs that told the public certain snakes were “poisonous” instead of venomous because too many people didn’t understand what this meant. This is also one of the reasons I left the field of research for education.

        This being said, and the reason I am calling it semantics is because the common person does not realize evolution does not happen to an individual, but a population. So while you are absolutely correct in point number 1 it is not debunking the diet, it is pointing out the incorrect use of terminology. However I would even argue that terminology is not entirely incorrect, because health definitely plays a role in fitness.

        I am curious, in writing this entry did you talk to any developers, followers, or scientists who support this? It seems like most of it was gleaned from wikipedia which can be a useful source for information, but if you are going to debunk something, you may want to get the side of those people making the claims and how they came to such conclusions.

      • Have you ever thought of trying the paleo diet? IBS is not a real disease, it is the catch phrase for when doctors can’t figure out what is wrong with you. Judging by your family history and your current state, I would wager 2 months of a strict paleo diet could change your life.

        As a scientists I love to experiment on my body to see what happens, from sleep deprivation, to a vegetarian diet, to a junk food diet, to high exercise program, no exercise program, to a paleo diet I have a good range of knowledge of my own body. I would like to see what you thought doing a STRICT 2 months of this diet.

      • Hird says:

        Hi again. You make a lot of good points, and I just want to be clear – I am not trying to debunk the diet itself. I have no expertise in the area of nutrition and it seems like the diet has done a lot of good things for a lot of people. I skimmed/read some of the primary literature from Loren Cordain (thepaleodiet.com/published-research/) and read a lot of the recent media coverage – nothing I read cited sources or provided evidence for the evolutionary part of the claims. If you know of an evolutionary biologist who has published research on this, I’d love to read those papers. In the grand scheme of things, though, I don’t think it helps anyone (lay person or scientist) to frame this diet as an evolutionary fact – because that’s not been demonstrated. It just confuses people about what evolutionary biology can and does say about human evolution and health.
        Personally, for controlling my “IBS” (yes, catchall term for “not really sure what’s happening”), I limit the amount of pasta I eat and I also limit the amount of meat I eat, because it’s a trigger food for me. Therefore, I can’t really imagine myself adhering to a diet that’s largely meat. However, I am intrigued about what the dairy aspect, so I might try to eliminate it entirely for a while and see what happens. (TMI? Who can say…)

      • I can get behind the statement of not calling it absolute fact. I think what triggered my defensive response was the word “debunk”. Which is ironic because of my previous statement about semantics….in my defense I read this when I first woke up and before I had my coffee (black of course, no sugar or cream, it is my one vice).

        While there might not be studies to show that it is factual, I also think there is not enough evidence to say there isn’t truth behind it.

        As for your triggers, I would wager dairy is a definite one. However I would be surprised by meat. Have you ever tried plain meat with no marinade, condiments, or bread? When I cook chicken or beef the best I can do is some seasoning. No condiments or marinades. I also discovered through research that a lot of doctors miss a gluten intolerance. I had to get blood work, which showed nothing, then I requested an endoscopy and colonoscopy to get a biopsy. Sure enough their showed some inflammation in my intestines, he said it was not celiac, but a gluten intolerance.

    • noahmattoon says:

      I think the point of the post is not to say that people cannot be healthy following the paleo diet, or even to attack the composition of the diet itself, but to point out that the evolutionary justification for the diet (which is often presented as the primary justification) is logically and factually flawed.

      I think with respect to gluten intolerance, it’s obvious that a large number of people have problems, that those problems have been under-diagnosed, and those people need to avoid eating wheat. But is it because people haven’t evolved to consume wheat? I’m not sure that claim has evidence to back it up. Interestingly, the incidence of allergies and autoimmune disorders in general is on the increase, and a major competing hypothesis explaining that trend also has an evolutionary component (http://fooddrugallergy.ucla.edu/body.cfm?id=40). I won’t get into it here, but that hypothesis could easily explain away high incidence of allergies of all kinds without invoking evolutionary maladaptation to modern dietary components.

  6. Lastly it should be noted that the agricultural revolution led to the overpopulated earth we are today.

  7. [...] ground-up rhino horn, threatens endangered species The Results are In: Scientists are Workaholics The beef I have with The Paleo Diet How do science blogs change the face of [...]

  8. octoploid says:

    Evolution also adapted our species to live outdoors naked. Why don’t advocates of the Paleo diet call for this too?

  9. Humanity’s genes have changed in the last 10,000 years. Read “The 10,000 year explosion”, by Cochran and Harpending.

  10. Read You says:

    How linear…

    Fitness is a bit more complicated than passing on multiple baby’s in one generation. Fitness by generations changes based on adaptability, as epigenetics change just as much if not more than mutations occur. In other words fitness is better measured over say at least three generations when looking at the introduction or removal of different foods, habits, etc.

    Also having a lactose gene turned on doesn’t per say make milk healthy for you; you just don’t shit your pants unexpectidly. That may play a role in fitness…

    Let us take a poke at some history. Coastal people in the America’s pre-european were taller, leaner, more muscular, people with much less signs of disease, cavities, etc. Inland you find shoter, fatter, less developed, more cavities, and signs of cardiovascular disease in skeletol remains. A Paleo diet person would argue it was because they ate grain (corn in this case, no one cared about quinoa) but there are a lot of possibilities that are not associated with ego confirmation of diet choices. First how do we know it had anything to do with consuming grains and wasn’t because they didn’t eat fish? All coastal people throughout all of history in general show signs of being healthier people (not fitness, but sometimes). Next how do we know that it was “grains” because what if they chose to eat Quinoa instead of corn; would they of shown the same problems? From a scientific stand point it could be said that Quinoa would of been a better choice since it doesn’t interfer with insulin reception like corn does. (but we only measure things based on glycemic index, and ignore hormone function)

    We have to consider other possiblities too. Who said humans evovled to eat specific things in specific areas? I’m sure it happens/ed but that isn’t the only way evolution “thinks” of how to deal with concerns in order to keep fitness up. If we are going to base our believes in philosphy then we need to know the opposite is true that we evovled to eat specifics. The opposite would be that we evovled to eat unspecifics…. That is contradictory. Going on a whim for a good idea has merits and limitations. No Paleo person can argue we achieved evolutionarily the ability to subsist well off of specific things, than that we achieved evolutionarily the ability to tolerate a wide array of food to be adaptable and nomadic. Now this part becomes comical… Prior to agriculture people moved around a lot because there wasn’t anything to tie themselves down. Maybe they only moved regionally but say you climb 7,000 ft in two miles, you are going to find some different food. Even in this article there is the point that between two different coast lines you have drastically different avaliable food sources!

    Fitness is complicated too. Should we judge ourselves based on it? Probably not… People that study fertility know that babies fly out of women post-famine. That is a bad thing because post-famine the epigenetic expression is usually not ideal among the people. We have great examples of that. Psychologically speaking people in hard times and under stress will express emotions for increasing their fitness at a higher level in order to solve the predicament that gives them anxiety. A confident healthy (coastal?) person may not even concieve because they biologically are so confident that their fitness ability isn’t even in question.

    But I support criticism of the Paleo diet, or any diet based in philosophy at heart. As the head in the field of health – as far as I’m concerned – said,

    “Most Paleolithic proponents are living in a romanticized delusion. Almost all of most recent ancestors, just about all around the world, ate less protein that we do, not more. Most vegetables and fruits eaten by paleolithic dieters were originally loaded with phytotoxins that those terrible grain-drunk neolithic idiots were actually smart enough to hybridize out of the wild type strains.” – Dr. D’Adamo

  11. noahmattoon says:

    some adherents of the paleo diet have picked up on and are discussing the post at:

    http://www.reddit.com/r/Paleo/comments/za9jb/the_beef_i_have_with_the_paleo_diet_nothing_in/

  12. Hird,

    I think your article is well-reasoned and well-written, but unfortunately, many of the facts/ideas that you reference about the Paleo diet are either outdated or very fringe.

    Just as an example, I’m heavily involved in the Paleo community and I don’t know a single person who thinks lean meat is the way to go. Loren Cordain (one of the “founders” of the Paleo movement) used to believe this and propagate it, but he hasn’t supported that position for quite some time. Within the Paleo community, fat is actually revered.

    I point out the lean meat/fat distinction not because it’s particularly important, but mostly because there’s a ton of misunderstanding about the Paleo movement in general, and it’s unfortunate that your otherwise well-reasoned and well-written article relies on poor information about Paleo.

    In terms of evolution optimizing health, there are likely some Paleo dieters who believe this. After all – as I’m sure you know all too well – evolution is not properly understood by the general public. However, anyone who writes about Paleo, particularly people like Robb Wolf, Mark Sisson, or Chris Kresser (probably the 3 biggest names in Paleo currently), consistently emphasize that evolution is all about fitness.

    Most importantly, because evolution is all about fitness (and because there is no ‘single’ Paleo diet), Paleo may use evolution as a starting point for hypotheses, but every recommendation is based in science rather than history. For instance, the fact that humans have only eaten grains for about 12,000 years or so is really only a starting point. Among other things, grains are nutritionally very poor – especially once cooked, grains are high in insoluble fiber and (generally) oligosaccharides that alter human gut flora in very unwelcome ways, and in folks with metabolic issues, the high insulemic effect of grains is a problem. (The grain industry would love for us to believe that grains are nutritious, but it’s just factually incorrect when compared to pretty much any other food, particularly meat.)

    By the way, the lists of Paleo foods that you linked to are crazy-fringe. No one in Paleo thinks diet sodas are Paleo at all, and dairy is a very gray area for Paleo. Fermented raw dairy is tolerated well by many people and has many good nutrient qualities, but mainstream dairy often anecdotally correlates for many people with gut issues and increased inflammation.

    I don’t comment much on articles, but after reading your post, I actually get the feeling that you’d LOVE Paleo if you read a bit more about it. Pretty much everything you disliked about Paleo actually isn’t true of Paleo, and the reasoning behind your article is firmly in line with current Paleo thinking.

    Thanks!

    Jeremy

    • Hird says:

      Hi Jeremy – thank you for such a polite (and thoughtful) response. I read many of the comments on the reddit paleo page and it’s refreshing to not be dismissed as an idiot. The more people read this post and talk about it, it seems to me this is a “marketing” issue. It irks me (on a personal and professional level) when I hear popular news sources bringing evolution into this as if the evolutionary science is fact and it annoys adherents of the diet that I haven’t tried it or acknowledged the nutritional science behind the diet (which seems to be non-trivial but I am not fit to adequately judge the science of).
      Thanks for the links. I browsed them all very quickly – the first sentence on Wolf’s website claims his diet “works with your genetics” and Sisson’s “Start here” page says “the human genome…only thrives under similar conditions” (where he means similar to the living condition of our ancestors). These statements are what irk me and I can’t find any actual evidence for statements like these. However, Kresser’s website and rhetoric sound very reasonable and I would be more supportive if all people spoke like him: “.. although observing the diet of our ancestors is an excellent starting place, it’s just that – a starting place. The fact that a food did not exist in the Paleolithic area is not alone a justification for not eating it. This is where modern science comes in.” Hooray for modern science!
      I think the bottom line is that diet/dieting is a big, big business and even people with good intentions and good nutritional SCIENCE need a hook to sell something. (Maybe that’s why the only links to food lists I could find were fringe? The most popular guys want to sell their lists instead of put them out there for free.) As a blogger, I guess I can’t really hold “the hook” against people. BUT I’m not going to stop being irritated at the misuse of evolution. Or does the Paleo Diet do something for irritability? Maybe I will look further into specifics :)

      • OK, now I can agree with you. I think my original annoyance was with the “debunking” and seemingly attack on the diet. Yes, I agree it is largely marketing, but like anything you need to weed through it to get to the root.

        Funny you should mention irritability, yes, it absolutely does. Before I started the paleo diet I was up and down with moods throughout the day. Wake up cranky in the morning, spike in happiness with a sugary breakfast, crash, spike at lunch, crash, etc.

        Then I went on the paleo diet, I don’t remember exactly when it happened, but my fiance tipped me off one morning when I was signing myself out of bed and she rolled over and said “What are you so happy about?”. I didn’t know, nothing different happening that day, but for some reason I couldn’t find a reason to be annoyed. Then it just didn’t go away. Don’t get me wrong, I get annoyed with things still, but legitimate stuff, not the “getting out of bed” or general short fuse anymore.

        More so, my days were not up and downs, but just a steady good mood. I was shocked by how much diet plays a role in our emotional and behavioral state.

        I am not sure if you are a fan of Radiolab, but Carl Zimmer tells an interesting story about the importance of good gut health and how it can make people more determined….

        http://www.radiolab.org/2012/apr/02/gut-feelings/

      • Hird says:

        thanks for the radiolab link, paleolithicromano! sounds interesting.

  13. Lol – I like the irritability line.

    I wouldn’t disagree with what you’ve said at all. It may largely be a marketing issue, and I personally think that some of the marketing needs to be updated.

    Lately, most of the scientific and research focus within the Paleo community is on the epigenetic consequences of various nutritional choices. You no doubt know way more about this area than I do, but it seems like DNA methylation is an important and ripe area for more research to figure out how various environmental factors affect us.

    (I would have just posted a reply by the way, but it seems like because I logged in through twitter, I couldn’t log in to reply.)

  14. Reblogged this on beersandtears and commented:
    Fad diets, misapplied science and the media reporting on nonsense. Check it out.

  15. jripplinger says:

    Sarah,
    This is a great post! We’ve been looking for a better way to eat since our second son was diagnosed with multiple food allergies and the evolutionary justification for the paleo diet seems very weak. It’s very funny that a google search for “paleo dieters don’t understand evolutionary biology” lead to a blog post by a former classmate. Small world.

  16. When has main stream media ever reported anything in an unbiased way, they just want to make stuff sound outrageous :)

    As a person concerned about my health, I am one of those people that has been in slight pain for 40 years minus a year when I cut everything out of my diet. Primal eating has been a savoir for me. I know it isn’t how they ate but it is damn closer than the processed wheat, corn, soy and sugar diet most people survive on. Does the standard american diet have a scientific basis, I think not, it is determined by what the big corporations think they can sell.

  17. [...] our ancestors did just after they came down from the trees, which I guess is the standard—right, Sarah?), but I think we can all agree it would be absurd and wrong to try and eliminate them from our [...]

  18. This article really sparked a lot of discussion from different standpoints. I have been on paleo for a few months now and I would say that the diet benefited me a lot. However, I do not follow a strict paleo diet- like totally eliminating grains or carbs on my lifestyle .I give in to my carb cravings every now and then. My stand on paleo diet and/or any other “diet” for this matter is that if you feel good about it then it must be right.

  19. […] from CJ. Since then, we’ve written about everything from mammoth extinction events to diet fads, from the rationality of science denialism to the selective effects of agriculture—and […]

  20. simplulo says:

    What I find convincing about the paleo diet (lower case) is not just the strength of the arguments for it but the weaknesses of the arguments against it, and this article has nudged me a step further in the paleo direction. The paleo diet is not trademarked or defined by a single book, individual, or organization. It is a general approach, whose principles I would express thus: the human animal evolved over a relatively long period of time (many hundreds of thousands of years) in a relatively stable environment eating a relatively stable diet, to which the individuals in the many human populations are generally adapted, and 10K years ago this diet began to change radically, while the human genome has changed relatively little (more among some populations, less among others), with a currently unknown contribution from the gut microbiome. Admittedly some paleo advocates speak with excessive confidence and certainty about a single, narrow ancestral environment and diet, and draw excessively strong conclusions from that about what one should eat, but the author is attacking straw men when holding them up as the one true paleo voice.

    If you owned an expensive animal (say a show horse or dog, or a panda or other exotic) and wanted to maximize the number of its offspring for sale, how would you go about determining its diet? The first question you would ask would be, “What does this animal eat in the wild?” You might also crunch some statistical data compiled from the experience of other owners, but with caution. Recycling ground-up cow offal into cow feed might boost protein and cow growth in the short term, but it doesn’t take a scientist to call that unnatural, and predict eventual consequences. We can think about other animals practically and objectively, but when it comes to ourselves all our emotions and biases come into play.

    Addressing the author’s three points:

    1. Yes, of course evolution acts to optimize evolutionary fitness (*long-term* reproduction), and so YES, it therefore acts to “optimize health” (awkward expression, that), and YES, well past childbirth, and even well past the child-bearing years in the human species, a very social animal. While we cannot *prove* that women live longer than men in order to assist raising grandchildren, casual observation suggests that grandparents, especially grandmothers, do traditionally play a significant role (making “affordable childcare” a perennial political issue in the modern world). Grandparents are the extreme case, but more obviously parents need to live a decade or two past the birth of the last child in order raise and protect it. OK, there are some animals that die soon after reproducing (male preying mantis, male black widow, other spiders). The line that connects health and evolutionary fitness might not be perfectly straight, but I’ll bet it’s straight enough. There are all kinds of studies showing how individuals attract mates by displaying their health, from owl calls (correlated with parasite load) to human dancing and facial symmetry. Clearly potential mates value that health for a reason. Like modern engineers, evolution probably builds some margin into its designs: an animal functioning at the edge, just barely healthy enough to reproduce, would be eliminated by any negative change in the environment. It is pretty unscientific to cherry-pick a single negative health trait, e.g. obesity, show a possible short-term correlation between it and short-term evolutionary fitness (number of direct offspring), and say health doesn’t matter.

    2. Yes, homo sapiens is an omnivore, but that silly word means only “eating both plants and animals”, quite different from its misleading etymology (“devourer of everything”). We clearly don’t eat “everything”, and clearly not in all possible combinations and proportions. I suspect that you will see diet patterns in other omnivores (under the popular definition of having a relatively broad diet) like dogs, bears, and pigs. Yes, various hunter-gatherer human populations might have varied diets, but they still didn’t eat modern crap. The fascinating book The 10,000 Year Explosion corrected my misconception that homo sapiens has not evolved over the last 10K years–in fact, evolution has been accelerated by higher selection pressure and increased mobility–but 10K years is still a short period. Yes, we *can* digest milk into adulthood, but knowledge that this a relatively new ability suggests that we reduce the amount of cow milk in the diet.

    3. No, we CAN infer what we ought to do based on evolutionary reasoning. Obviously scientists, needing to prove things to their peers, will insist on higher standards for themselves. The rest of us, who have to make real dietary decisions today, can’t wait for the results of studies to roll in. The paleo principle is plausible, parsimonious, aligned with existing scientific opinion on evolution and diet, and not the result of some food-industry lobbying effort. You go ahead and wait for scientific proof–I’m going to make my decisions today based on mere evidence, a convincing argument, and the absence of convincing counter-arguments. “For example, lean meats good, fatty meats bad. Paleolithic humans probably ate fatty meats every chance they got, don’t you think?” Sweet, this is paleo thinking, correcting a possible misconception of some paleo advocates. There is hope for the author after all.

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