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I am a politically-progressive, ethically-herbivorous anthropoid pursuing a paleontology education in the Los Angeles Basin. I am largely nocturnal, have rarely been photographed, and cannot thrive in captivity.

09 December 2011

A Definitive Critique Of The Paleo Diet

Debating paleo dieters is often like debating creationists: sometimes, it's hard to know where to begin, their misunderstandings of evolutionary theory are so fundamental. When dealing with both crowds, I often feel I need to teach them a remedial course in evolutionary biology just to make sure words mean the same things to us. It's wearying and, for an undergrad like me, often a complete waste of time.

But thankfully, someone has taken the time to assault the entire paleodiet ideology from its foundations all the way up to its particulars. Below is the first installment of a brilliant video series by a YouTuber who goes by the handle of Primitive Nutrition. It'll give you a taste of how deeply paleo dieters misunderstand the basics of science and the major concepts in evolution. At the time of this post, I've watched four of the guy's videos, and am mightily, mightily impressed.

Watch the whole series. I'm going to, cuz I suspect it's worth every minute.

33 comments:

  1. Did you really watch the whole thing? Really? I'm as skeptical of paleo folks as you are, but the ones I watched were full of strawmen. Besides, vegan is not the best choice because it's a superior diet, but because of what it does for animals. We lose when we start to argue it's the best diet.

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  2. I'm in the process of watching it all the way through, but I haven't spotted any significant straw men.

    Also, he's not arguing that veganism is the best diet; in later videos, he makes clear that the very idea of "best diet" is nebulous at best, if not actually impossible.

    It bears watching all the way.

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  3. What exactly do you think paleo supporters are missing?

    You really think this video is good?

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  4. I tried watching one of his videos but his logic is horrible. This dude could prove to himself that the hollocaust never happened, or that we never landed on the moon....

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  5. Simple, Jared. Paleo supporters do not understand evolution, and their claims based on it are bogus.

    What, specifically, are you alleging that he gets wrong?

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  6. I'm a paleo supporter. Are you saying I don't understand evolution?

    I tried watching the low-carb diet video. It's horrible. Not to mention him ignoring the 12 or 13 clinical trials in the last 15 years showing greater fat loss for low-carb diets over other diets.

    As someone else said here, straw men are just some of hte problems. It's impossible to listen to this guy because he isn't a logical person. He thinks he can prove things that he can't possible show. No one can.

    What exactly do you think I don't understand about evolution?

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    Replies
    1. "I tried watching the low-carb diet video. It's horrible. Not to mention him ignoring the 12 or 13 clinical trials in the last 15 years showing greater fat loss for low-carb diets over other diets."

      Could you link me these studies Jared?

      I don't think Plant positive is saying low carb isn't a good weight loss diet. He's saying it's probably not the healthiest even though it's in many ways better than SAD.

      Delete
    2. Weight loss, regardless of the method, tends to improve health biomarkers. So I wouldn't write this off as completely irrelevant to Plant Positive's message. If someone can lose (and keep off) significantly more weight on a low-carb diet than on a high-carb diet, then there's reason to believe that the low-carb diet may actually be healthier for him/her.

      Delete
    3. Hi DarkLixuz,

      I don't know if these are the same studies Jared is referring to, but here is a list of 14 clinical trials showing superior weight loss on low-carb diets:

      http://www.awlr.org/carb-restricted-diets.html#LowCarbWins

      Delete
  7. Jared,

    I suggest you start the video series from the beginning, as the first 14 of them cover evolutionary biology in detail. I didn't spot any straw men there.

    As for what you don't understand about evolution, it would be hard to say specifically without further dialogue. Why don't you explain your rationale for being a paleo supporter and how evolution informs that rationale, and we'll see?

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  8. Why would I watch more videos by someone who cannot reason in a logical way? I don't watch videos by 9/11 conspiracy theorists either.

    If you don't think the paleo diet is supported somewhat by evolutionary reasoning. Which diet do you think is more supported in this context?

    Evolution is at the core of the paleo diet. It's genesis is in biological anthropology. What kind of dieters would understand evolution better?

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  9. Jared,

    Well, see, there you go. Your first question is nonsensical from an evolutionary biological standpoint. The idea that evolution has a diet in mind for us is ridiculous.

    It's all chemistry in the end. Your body does not care where its nutrients come from. There's no gene for specific diets.

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  10. Well you're putting words in my mouth. I never said that evolution has some perfect diet in mind for us. Of course it doesn't. People can survive/thrive on a variety of foods.

    This doesn't mean that evolution doesn't give us a tool for developing hypotheses as to which foods we are more or less likely to be adapted to eating, e.g. grains, vegetable oils, etc.

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  11. Fair enough, Jared. Give us an example of such a hypothesis, and we'll see.

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  12. The Humane Hominid,

    "The idea that evolution has a diet in mind for us is ridiculous."

    This is already a strawman, and one of many strawmen he attacks. While this used to be a valid criticism of the paleo diet movement, that is no longer the case. Current paleo thinking is that there are a wide spectrum of paleo diets, and any one of them can be considered "paleo." Furthermore, paleo dieters now tend to acknowledge that diets should be catered to the individual, and that there is something wrong with trying to force everyone to eat the same way. As evidence:

    http://chriskresser.com/beyond-paleo-moving-from-a-paleo-diet-to-a-paleo-template
    http://www.archevore.com/panu-weblog/2011/3/30/paleo-20-a-diet-manifesto.html
    http://freetheanimal.com/ancestral-life-way (see bullet #4)

    The video makes a big deal about how paleo is not a scientific theory, but merely a hypothesis. I don't think most paleos would argue, or even care, about that issue. Paleo dieters discuss a "paleo principle," which is essentially a blueprint for you to identify potentially problematic foods. Obviously that list would include grains, legumes, and dairy. But again, it is not dogmatic -- some "paleo"-style bloggers eat white rice (Melissa McEwen, Kurt Harris, the Jaminets, ...)

    This video series focuses a lot on low-carb paleo (I've only watched 6 videos so far), but at this point I would say that high-carb paleo is quite a sizable contingent in the community. The idea that paleo diets MUST contain a lot of meat is false -- meat continues to be a focus of discussion simply because it is so commonly demonized in the mainstream media. High-carb paleos don't necessarily go crazy on the meat.

    It is unfortunate that he chose to analyze Cordain, because Cordain's views on saturated fat are in the minority among paleo folks. The video series tries to paint this imagined high-protein vs high-fat schism, but it's really lopsided. Cordain is essentially the only holdout left in the anti saturated fat camp. Low-carb vs high-carb would have been a much better example of a REAL divide.

    "Your body does not care where its nutrients come from. There's no gene for specific diets."

    Don't you think it's reasonable to believe that the body handles nutrients best when it comes in the types of packages typically seen in nature? These are the general nutrient combos your genes have been selected to recognize & expect. Therefore, it may be best to eat these nutrients together.

    For example, consider the fat-soluble vitamins. They synergistically improve the bioavailability of each other, and their absorption is further strengthened by the presence of dietary fat. In nature, they all tend to occur in the same package -- animal fat.

    There's a lot of finger-pointing at fructose these days. Lustig believes that fiber is the antidote, which is why fruit sugar is ok. But only if you eat fiber and sugar together -- fiber supposedly slows the rate at which fructose pounds the liver.

    So in this sense, I'd say your body *does* care where its nutrients come from. There may be certain "packages" of nutrients (discovered or as-yet undiscovered) that are better digested/absorbed synergistically.

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  13. Will, let's agree we shouldn't eat refined foods. Fair? So let's not pretend we are having that argument. I agree with you, your body cares about the form of delivery of nutrients. I have a sequence addressing multivitamins and elemental feeding which makes this point. Did you miss it? The point about your body needing nutrients is that that isn't the primary concern of diets branded as "paleo". Paleo means avoidance of dairy, grains, and legumes. That is the point, as stated in the first video, so it is you who is taking this information out of context to fashion straw man arguments.

    Your "paleo principle" is, unlike the claims made by Cordain, not scientific. It's just a rule of thumb that you like. No one can tell you what to do. The videos are simply to address the faulty science and logic surrounding Paleo. True, most followers of these diets don't care much about the scientific claims. They probably really just like the paleo story, but that's just my guess.

    Yes, other people are doing all manner of diet strategies and calling it paleo or primal or whatever. I don't really care about the label. As the Truthiness section makes clear, it's inherently vague. If you want to approach diet like Don at Primal Wisdom or be a fruitarian or something else entirely and call it paleo or caveman or macho or super-manly-man-biceps diet, that's up to you. Enjoy yourself.

    I don't think you understood the sequence on fructose. I could say protein pounds the kidneys but it's a matter of degree, isn't it?

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  14. Obviously that list would include grains, legumes, and dairy.

    Sorry, I don't get what you mean by this. Are you saying that paleo is obviously defined by its categorizing these foods as problematic, or that paleo excludes them for some obvious reason? If the latter, I don't see what's obvious about it at all.

    Don't you think it's reasonable to believe that the body handles nutrients best when it comes in the types of packages typically seen in nature?

    Not particularly, no. As I said, it's all chemistry in the end. Any substrate that delivers the right dosages of the required nutrients will do the trick. Your body does not care whether the delivery system is vegan, paleo, SAD, or anything else.

    For example, consider the fat-soluble vitamins. They synergistically improve the bioavailability of each other, and their absorption is further strengthened by the presence of dietary fat. In nature, they all tend to occur in the same package -- animal fat.

    Fat-soluble vitamins -- particularly vitamin A -- carry a greater risk of toxicity precisely because they are concentrated in the fats of animals. Most nutrition and health professionals recommend getting vitamin A indirectly through carotenoids for this reason.

    All of the fat-soluble vitamins are available from non-meat sources, and they are stored in the liver for long periods of time until needed. Even if I grant that animal fat is the "best" package for delivering them, the fact that we store them for later use could easily be used to construct a just-so story claiming that we evolved this storage mechanism as a response to prolonged periods of animal fat deprivation, implying that we didn't really eat animals all that often.

    But that would be speculation at best, as are most "paleo" claims about diet that I've ever seen. Undoubtedly, there is an evolutionary explanation, but experience teaches us that it's probably not the one that seems obvious to us.

    As for the rest of your post, I don't think the diversity of paleo thought is a valid critique against this guy's series. He's addressing specific claims made by various paleo proponents, and points out that he's focusing on Cordain because he thinks Cordain is the most credible of all of them. His critique isn't based on the assumption that Cordain is necessarily representative of the whole movement, or even that the movement has a unified interpretation of the evidence. Rather, he seems to be saying that if the assumptions of paleo are correct, there ought to be more consistency in its health and nutrition claims.

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  15. Plant Positive,

    "Paleo means avoidance of dairy, grains, and legumes. That is the point, as stated in the first video, so it is you who is taking this information out of context to fashion straw man arguments."

    Huh? I'm confused. My nutrient comment was not a straw man argument. It was addressed at The Humane Hominid, not you, your videos, or the paleo diet. It's a belief I think HH has previously expressed elsewhere on his blog. HH also responded by confirming that this was his belief. You and I happen to _agree_ on this point (in opposition to HH).

    "Your 'paleo principle' is, unlike the claims made by Cordain, not scientific."

    It isn't _my_ paleo principle. I didn't make it up. I am not even a paleo diet evangelist, as you seem to assume. (Gave it up 8+ months ago.) Nor am I a vegan evangelist, for that matter.

    Go ask on paleohacks if the "paleo principle" is a scientific theory or a merely rule of thumb. I believe (though I'm not 100% certain) that nobody is claiming it to be science. It is simply a practical tool for guided self-experimentation. What's so bad about that?

    "True, most followers of these diets don't care much about the scientific claims. They probably really just like the paleo story, but that's just my guess."

    I agree with your claim that Cordain's "paleo diet hypothesis" is pseudoscience. So it isn't worth debating if that was the scope of your video's intent. But this fact alone would not faze a lot of paleo advocates. They do care about scientific claims, but Cordain's hypothesis is hardly a centerpiece. The bulk of their supporting science is not Cordain's pet hypothesis, but instead has to do with... nutrients! Those dastardly things you thought were not a primary concern of the paleo diet. :) In particular, fat, saturated fat, cholesterol, CLA, EPA/DHA, grain lectins, phytates, enzyme inhibitors, etc. Now, the strength of each of these arguments in support of a paleo diet may vary, but they ARE grounded in real science, not pseudoscience.

    Your second observation is correct, by the way. IIRC, Robb Wolf (who has done far more than Cordain to bring paleo to the masses) has said that the paleo story is very effective at getting buy-in to the concept.

    "Yes, other people are doing all manner of diet strategies and calling it paleo or primal or whatever. I don't really care about the label. As the Truthiness section makes clear, it's inherently vague."

    NOW we're getting somewhere. :) This is my #1 complaint about the paleo diet. Over the past year it has basically morphed into a gluten-free version of the "real foods" movement (if you take the union of all of its fragments). It consequently doesn't have much to offer beyond what already exists. Kind of lame, but really not that harmful per se.

    What bothers me more about this paleo "identity crisis" is the fact that people new to the paleo community will start adapting outdated paleo practices for reasons that were already disproven.

    "I don't think you understood the sequence on fructose. I could say protein pounds the kidneys but it's a matter of degree, isn't it?"

    Ummm, I did mention in my original post that I only watched the first 6 videos, right? Your series only just entered my radar last night when I saw Don Matesz's blog post. There are *71* videos! Give me a break here :) Ditto to your comment about the multivitamins and elemental feeding sequence.

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  16. The Humane Hominid,

    I will get back to you later. I used up all my glucose right now by replying to Plant Positive. :P

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  17. Will, thanks for this. I would appreciate it if you would relate specific examples of any fallacies you believe I've committed.

    "This is already a strawman, and one of many strawmen he attacks."

    Please elaborate. If I've made errors I'll acknowledge them. I think this only seems like a strawman to you because I am addressing Paleo literature and beliefs that don't interest you. It does seem to be a central tenet of Paleo that there is a diet in our genes, based on my reading. The Paleo dieters I've encountered are eating a hell of a lot of meat. I wonder how many self-identified high-carb paleo dieters are out there.

    As you watch the series you'll see my take on these specific nutritional issues. I believe they are raised only to bolster the Paleo concept, and are not dealt with responsibly.

    "It is simply a practical tool for guided self-experimentation. What's so bad about that?" The problem is the word "paleo", which is fraught with pseudoscience nonsense. A "whole plant food principle" would be a far more responsible model for self-experimentation.

    Thanks for your interest in my videos. I hope you enjoy the rest.

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  18. I enjoyed the 71 part Primitive Nutrition video series.

    However, it should have included a mention of Dr. Walter Kempner and his use of a diet consisting primarily of white rice and fruit to deal with chronic kidney disease and hypertension.

    Kempner was a refugee from Nazi Germany and ended up at Duke University. In the 1930s he had come up with the idea that by creating a diet that was low in protein and low in sodium, the workload of the kidneys would be reduced.

    Kempner ended up with a white rice and fruit diet (often called "The Rice Diet"). In this diet protein was often restricted to be as low as 20 to 35 grams and sodium was often restricted to be as low as 125 milligrams.

    (In those early days (1930s-1940s) there were no anti-hypertensive medications.)

    Kempner's rice diet ended up not only proved to be very effective at dealing with renal insufficiency and hypertension, but also cardiovascular disease, type 1 and type 2 diabetes and obesity.

    Consider that while most of today's advocates of a plant-based diet, correctly, mention that they do not support a diet high in refined plant based foods, Kempner's Rice diet featured a refined plant based food: White rice.

    Do the Paleo folks who say that grains are bad for us know about Dr. Kempner's rice diet?

    I think if this video series had included a few mintues of Dr. Kempner, it might of added a bit more data for the viewer.

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  19. The Humane Hominid,

    "Are you saying that paleo is obviously defined by its categorizing these foods as problematic, or that paleo excludes them for some obvious reason?"

    The former. Simply speaking, orthodox paleo excludes these food categories.

    "Any substrate that delivers the right dosages of the required nutrients will do the trick."

    What do you think of replacing real foods with supplements? Based on the above, it sounds like you would have no problem with this idea -- contrary to the advice of both vegan and paleo promoters. Why not just supplement nutrients and forego eating kale? Because, let me tell you, I am no fan of kale. (I know, Joel Fuhrman is crying right now, nutrient density table in hand.)

    "Fat-soluble vitamins -- particularly vitamin A -- carry a greater risk of toxicity precisely because they are concentrated in the fats of animals."

    Vitamin A toxicity is in most cases a downstream symptom of vitamin D deficiency. Vitamin D protects against vitamin A toxicity and vitamin A protects against vitamin D toxicity. I would say get sunlight, but I guess you would reply that vitamin D supplementation is equivalent. :)

    Getting enough vitamin A and D also increases the need for vitamin K2. Whole natural animal foods tend to provide vitamins A, D, and K in the same package. This interaction between food components is exactly why Campbell prefers a holistic view of nutrition and health.

    "Even if I grant that animal fat is the 'best' package for delivering them, the fact that we store them for later use could easily be used to construct a just-so story claiming that we evolved this storage mechanism as a response to prolonged periods of animal fat deprivation, implying that we didn't really eat animals all that often."

    I don't think this is incompatible with my statement.

    Plant Positive,

    I would go back and review the sequences I've watched for fallacies, but I'd much rather finish your series first. :) Despite the fact that I wrote only negative feedback, I've actually quite enjoyed the series so far and I agree with many of the points you've highlighted.

    "The Paleo dieters I've encountered are eating a hell of a lot of meat. I wonder how many self-identified high-carb paleo dieters are out there."

    This is a good point. I would guess that nearly all novices approach paleo with the impression that it is low-carb, due to outdated advice from books like The Paleo Solution (Robb Wolf is now more accepting of high-carb approaches). This is in contrast to the more experienced members, where there is a noticeable split between high-carb and low-carb. Among the leading thinkers there is also a split, but from my vantage point the low-carb tide is shrinking.

    Emerson,

    This therapeudic effect is not limited to the rice diet. Even high-meat paleo diets tend to improve hypertension as well as risk factors for diabetes and heart disease for many people. I attribute these effects primarily to weight loss, regardless of diet. Just because Kempner's diet improved biomarkers does not mean it is the only diet (or the optimal diet) capable of doing so.

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  20. Emerson,

    It occurred to me that I wasn't addressing your real point (I created a straw man. Guilty as charged :D), which was "if grains are so bad, why does the rice diet work?"

    Paleo dieters consider grains bad due to their high antinutrient content, particularly gluten and IP6. Rice has no gluten and it's overall lectin content appears to be quite benign.

    In this view, refined (white) rice is actually _better_ than brown rice, because most of the phytic acid and lectins are removed.

    So white rice is unique among grains in being less "toxic" than even white potatoes (which contain a poison called solanine).

    As Kurt Harris says,

    "White rice is kind of a special case. It lacks the nutrients of root vegetables and starchy fruits like plantain and banana, but is good in reasonable quantities as it is a very benign grain that is easy to digest and gluten free."

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  21. Nice work plantpositive. Very impressed.

    1) In regards to grains, shift to agriculture and its induced height shortening. I have a problem. I think it's rather a false premise to sugggest that the European population at the time was unchanged. What is neglegted is immigration. At the eve neolithics Europe most likely experienced a new population wave from the Middle-East, followed by Bergmanns rule this new group of arrival was of shorter statute since they came from warmer climates.

    We don't see any evidence of height reduction at the edge of Europe, in the present day area's that belong to Portugal these days, f.e. This could suggest that these peripheral parts did not receive substantial immigration. This issue, neolithic immigration to Europe is something we are slowly starting to learn thanks to population genetics.

    2) Paleo-crew's idea that grains as such caused the reported health decline in Europe is very far-fetched. The authors this paper, although still goin' by the unchanged population hypothesis, explain the temporary health degration through seasonal hunger, reliance on single crops deficient in essential nutrients, crop blights, social inequalities, and trade

    Stature and robusticity during the agricultural transition: Evidence from the bioarchaeological record.


    Mummert A, Esche E, Robinson J, Armelagos GJ.


    Abstract
    The population explosion that followed the Neolithic revolution was initially explained by improved health experiences for agriculturalists. However, empirical studies of societies shifting subsistence from foraging to primary food production have found evidence for deteriorating health from an increase in infectious and dental disease and a rise in nutritional deficiencies. In Paleopathology at the Origins of Agriculture (Cohen and Armelagos, 1984), this trend towards declining health was observed for 19 of 21 societies undergoing the agricultural transformation. The counterintuitive increase in nutritional diseases resulted from seasonal hunger, reliance on single crops deficient in essential nutrients, crop blights, social inequalities, and trade. In this study, we examined the evidence of stature reduction in studies since 1984 to evaluate if the trend towards decreased health after agricultural transitions remains. The trend towards a decrease in adult height and a general reduction of overall health during times of subsistence change remains valid, with the majority of studies finding stature to decline as the reliance on agriculture increased. The impact of agriculture, accompanied by increasing population density and a rise in infectious disease, was observed to decrease stature in populations from across the entire globe and regardless of the temporal period during which agriculture was adopted, including Europe, Africa, the Middle East, Asia, South America, and North America.


    Best regards, Richard!

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  22. Richard, thanks for your support! These are valid points. I've since thought of a few other explanations as well, but I hope that section covered enough ground to provoke some skepticism of the Paleo claims. You're right, migration patterns are another consideration worthy of investigation. I encourage you to post a comment to this effect for that video or blog about it yourself.

    Take care!

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  23. Will,

    What do you think of replacing real foods with supplements? Based on the above, it sounds like you would have no problem with this idea -- contrary to the advice of both vegan and paleo promoters.
    You're absolutely right, I wouldn't. I am a vegan for ethical reasons, so I don't particularly care about nutritional arguments. I'm also a skeptic of "alternative' health claims (including The China Study, though not for the commonly-cited reasons).

    That said, I eat a mostly whole foods vegan diet and take a sublingual B-12 supplement a couple times a week. Science may one day make it possible to eat nothing but supplements, but we're not there yet. My only real point is that our bodies don't give a damn; they just want the nutrients in the right dosages, and could give a fuck-all about their source.

    Why not just supplement nutrients and forego eating kale? Because, let me tell you, I am no fan of kale. (I know, Joel Fuhrman is crying right now, nutrient density table in hand.)
    You have obviously not tried the official leafy green of PaleoVeganology -- dinosaur kale!

    Richard,
    Keep your eyes peeled. I'm actually working on a post right now about the "Neolithic" decline in stature. It'll have some scholarly citations, but here's a preview: it started long before the Neolithic transition, occurred in hunter-gatherer populations as well as agriculturalist ones, and wasn't limited to only humans. Hence, probably not caused by the switch to agriculture.

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  24. Interesting background on who this guy is and a response from Kurt Harris:

    http://www.archevore.com/panu-weblog/2011/12/13/don-matesz-stumped-by-tim-the-enchanter.html

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  25. @Plantpositive

    could you copypaste my response to the grain-thread. I would do that myself, but I don't have youtube account, and I am bit of short of time.

    Anyways, once again, beautifull work, it was pure rock&roll, every video. We'll see how this will be taken in the cavemen sphere :)

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  26. ^the above was from Richard

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  27. @Jared M Johnson

    You do realise Don Matesz doesnt make those videos? he just blogged about them.

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  28. Hi Humane Hominid,

    Thanks for the tip on dinosaur kale, by the way! I tried it shortly after your comment, and boy it tastes 1000x better than curly kale. It's one of my favorite leafy greens now.

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    Research in biology, biochemistry, Ophthalmology, Dermatology and many other disciplines indicate it is our modern diet, full of refined foods, trans fats and sugar, that is at the root of degenerative diseases such as obesity, cancer, diabetes, heart disease, Parkinson’s, Alzheimer’s, depression and infertility.
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    ReplyDelete