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Rationally Speaking is a blog maintained by Prof. Massimo Pigliucci, a philosopher at the City University of New York. The blog reflects the Enlightenment figure Marquis de Condorcet's idea of what a public intellectual (yes, we know, that's such a bad word) ought to be: someone who devotes himself to "the tracking down of prejudices in the hiding places where priests, the schools, the government, and all long-established institutions had gathered and protected them." You're welcome. Please notice that the contents of this blog can be reprinted under the standard Creative Commons license.

Tuesday, February 21, 2012

Dietary Pet Views


Guest post by Greg Linster

I recently saw the popular movie Forks Over Knives. In case you’re unfamiliar with its basic premise, the movie is based on the book The China Study, which was referred to as the “Grand Prix of epidemiology” by The New York Times. Essentially, the authors, T. Colin Campbell and Thomas M. Campbell, extol the alleged health benefits of a strictly “plant-based diet,” particularly one that is also void of processed food. Similarly, the movie champions the idea that a diet void of animal products is optimal to maximize human health. Perhaps not surprisingly given my nature, I found myself to be skeptical of this claim.

Before I proceed, however, I’d like to clear one thing up. I’m interested in eviscerating the health based reasons for avoiding all animal products that were provided in the movie, not in addressing the ethical reasons for avoiding animal products. People who choose to avoid animal products for ethical reasons are unlikely to be moved by empirically based health reasons, and I can certainly respect that choice.

So why exactly am I skeptical of the “plant-based diet is optimal” claim? I think that’s because I got the impression that the authors used science to promote their pet views, instead of using science to promote the truth. My basic problem with their claims is that they are predicated on an empirical approach that ignores important, yet subtle nuances in the functioning of complex systems like the human body and food digestive apparatus. It’s not, however, within the scope of this post to sift through all the faults with the empirical work used to promote these beliefs.  Instead, I will focus on one tacit assumption, which I believe is false, i.e., that all animal products are created equal.

There is a number of things about which I do agree with the movie’s perspective. I, like the producers, believe that diet and lifestyle are an important component of the overall general health picture. Also, I can get on board with the message the movie offers about processed foods, i.e., that processed foods are at least partly to blame for many of our collective health woes. Here are my reasons for this belief: in the evolutionary picture, processed foods haven’t been around for all that long, yet they currently make up a large portion of our diets. We also know that diabetes, hypertension, and certain types of cancer have dramatically increased in roughly the same time frame as the widespread consumption of processed foods. Based on the empirical work and the type of logic presented in the film then, I believe that removing processed foods does improve health, at least to some degree.

However, the movie also discusses a correlation between the absence of animal products and improved health measures. What do I make of that? We all know the hackneyed cliche that correlation doesn’t imply causation, although sometimes when two things are correlated, one of them is indeed causing the other. The problem is that it’s often easy to mistakenly get the causation backwards, or to ignore the presence of a third but unaccounted for critical element.

For instance, let’s assume that people report improved health markers when they eat fewer processed foods, which also means they eat less sugar. Let’s also assume that they eat fewer animal products too. In this oversimplified example, is it the removal of animal products that is causing the improvement in health? Based on the information provided in the example, we don’t know, and it is at least as possible that the sugar is the culprit instead of the animal products.

Here’s another interesting question: is techno-manufactured meat from sick animals bad for you? I happen to think so. Does this mean that all types of meat are equally bad for you? Not necessarily. My main issue with the movie’s producers is that they seem to demonize all forms of animal products, while ignoring that there are differences in the quality of meats out there. For example, the meat in a McDonalds hamburger is not of the same quality as that of a 100% grass-fed New York strip steak. If one were to eat McDonalds hamburgers every day, then get sick, it simply wouldn’t logically follow that all meat is thus unhealthy. After all, there are also studies showing that there are health benefits from grass-fed and pasture-raised meat. There is absolutely no mention of controlling for meat quality differences in the film.

For comparison, let’s look at a few interesting examples of various cultural dietary habits. On the one hand, the Masai live almost exclusively from their cattle and eat lots of saturated fat, all the while remaining free of Western diseases. On the other hand, there are groups of people, like the Peruvians and Kitavans, who eat massive amounts of carbohydrates (in the form of tubers) and also remain free of Western diseases. How can this be?

The bottom line is that causation is very difficult to determine in complex systems, like the human body. The medical establishment has, for decades, demonized saturated fat because of an alleged connection to increased heart disease. “What If It’s All Been A Big Fat Lie” though? In the carbohydrate versus fat debate, many people ignore the possibility that other factors, such as significantly reduced sugar consumption, are at play. The producers of Fork Over Knives only perpetuate the problem by ignoring this possibility.

Ultimately, movies like Forks Over Knives are explained by the fact that most of us like to take sides and join tribes. And of course we want other people to join our tribe! If we believe that saturated fat is good for us (or at least not bad for us), there is also a temptation to jump on the bandwagon of demonizing carbohydrates. However, this is problematic from a rational perspective because people the world over remain healthy on all types of diets with varying macronutrient contents. Perhaps what healthy people have in common isn’t what macronutrient they eat or don’t eat, but what specific manufactured crystalline carbohydrates (sugars) they don’t eat. So instead of worrying about what macronutrients to remove entirely from our diets, perhaps we should worry about removing processed foods and sugar from our diets.  And we probably should be consuming quality (grass-fed and pasture-raised) meats as well.


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Greg Linster is a graduate student studying the applied branch of philosophy called economics at the University of Denver. While he spends much of his time studying Homo economicus, he has a strong interest in behavioral economics as well. As an avid writer and inveterate reader, Greg also writes a blog called Coffee Theory and maintains a site called Aphoristic Cocktails, which is dedicated to the beautiful literary form known as the aphorism. His writing has appeared in several popular blogs and webzines, and also in the magazine Philosophy Now. Greg is particularly interested in examining the world from an evolutionary perspective and in practical philosophy. One of his chief goals in life is to try and be a philosopher while remaining a nice guy.

26 comments:

  1. I will continue to finish this post, but one thing jumps out at me that raises red flags. What exactly constitutes "processed foods", cooking is processing, so is grinding a grain into flour, and any number of things can be referred to as constituting "processed" food. So this concept needs to be unpacked and defined.

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  2. Sheldon,

    I agree that "processed food" is a nebulous term, so I think you bring up a great point.

    When I say I believe in avoiding processed foods, I'm referring specifically to products that have refined sugar, trans or partially hydrogenated fats, and anything with pesticides, herbicides, fungicides, preservatives, or other chemicals.

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  3. There are some obvious problems with the assumptions they pull. For example they compare heart disease, which is primarily a late-life disease, to that of countries with a life expectancy 15-20 years shorter than in the US.

    I'm a personal trainer, and I have a couple of clients who are high school kids. They've told me about their lunches, and it's awful – fries, pizza, fried chicken, soda, and virtually no fruits or vegetables at all. I don't think the problem in that sort of diet is that it contains chicken, amiright?

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  4. Hey Greg. If you want to read a thorough dismantling of the china study look up Denise Minger at www.rawfoodsos.com. Keep in mind it's a long read and full of data. But she basically goes through it with a fine tooth comb. At one point she got into an email debate with Dr Campbell. Pretty interesting read but I'll let you make your own decision on it.

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  5. Look up Denise Minger at www.rawfoodsos.com. She basically brings the hammer down on the china study, dismantles it piece by piece. She also did a critique of fork over knives. Its a long read but well worth it.

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    1. Sorry, I’m just not as smart as Denise Minger. I don’t have her level of expertise used to refute peer-reviewed studies done by accredited nutritional scientists, sponsored by Cornell University, the University of Oxford, and the Chinese government.

      Mind you, I’m not saying Forks Over Knives gets a free ride, but forgive me if I wait until peer-review retracts the China Study before declaring it “debunked” by an unaccredited rawfood blogger with a chip on her shoulder because veganism made her ill as a teenager by mechanisms yet to be discovered through conventional science even though vegan diets have been studied extensively.

      Yes, I have a tentative approach to these sorts of things, but it’s the strategy I used to evaluate climate science. Despite the peanut gallery Internet debunking, the peer re-review is in. It holds up. I’ll wait for peer re-review in the China Project case as well. I’ll wait for the report for the China Project II to finalize and we’ll see what we get. It will either substantiate the first research on some level, or completely contradict it if Campbell was just pulling the wool over our eyes. Just have to wait and see.

      Sorry, but if I don’t have the expertise, and you don’t have the expertise, peer-reviewed consensus science trumps amateur blog posts. Her blog is all very interesting, I applaud her efforts to a certain extend, but we have little reason accept it as correct.

      If she’s right, that’s fine, its one study among many and doesn’t really impact my worldview, mainly because the China Study doesn’t impact my worldview very much in the first place.

      In the meantime we all await her upcoming new book about how conventional nutritional science has it all wrong. Grains are probably poisonous, yada, yada.

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    2. Do you believe Denise Minger's critique is valid on its own merits? If so, why are so intent on attacking her credentials and character and not her ideas? Are you more concerned with who is doing the critiquing or the truth? I get the impression that it's the former. The fact that Denise Minger doesn't have credentials, does not mean that her claims are necessarily wrong.

      In my opinion, what should make us skeptical of experts in some fields isn’t always what they can say, but what they can’t say. For instance, Dr. Campbell has quite a bit riding on this hypothesis (namely his career and identity). Intelligent dilettantes aren't necessarily bound by the same constraints.

      Granted, in some fields expertise matters; however, in some fields there can be no experts. We're not talking about rocket science here. There is plenty of historical evidence showing that humans can eat meat and not suffer from Western diseases. If Dr. Campbell wants to make the claim that a plant-based diet is healthier (whatever that really means), then the onus is on him to prove it. Therefore, when he presents questionable evidence supporting a radical change in our diets it should be critically analyzed in depth.

      I'm curious about hearing your thoughts in other fields. Do you think "non-economist experts" (those without a PhD) should be able to critique the assumptions of neoclassical economics? Or do we need to wait for the world's most prestigious universities to quit teaching it first?

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    3. I don’t have the expertise to analyze the China Study data.

      I’m not attacking Minger’s credentials. I’m citing her lack of credentials and pointing out bias and motivation. You had a very similar response after I posted my first comment:

      “The most interesting part of any comment is the person's motivation for leaving it. Do you care to make your bias explicit?”

      There’s little to build trust that Minger’s analysis is wholly informed and there are many red flags that warrant reasonable skepticism. If I go into particular reasons why I don’t feel inclined to accept her as credible, I will just be told that I’m committing ad hominem, so I won’t bother further. Perhaps that’s a cop out but I don’t see why the burden of proof is on me to accept her analysis as valid. It doesn’t surprise me when people outside the skeptic community link information as de facto sources of debunking, but it’s disappointing to see it here.

      I’ve offered my reasons as to why I’m inclined to side with Campbell’s research until a more credible source overturns it. Again, I don’t need it to be true, veganism has existed before the China Study and the China Study doesn’t prove veganism anyway, so I feel as if I have an open mind. Why do you believe that Minger’s analysis holds weight? We’ve got “intelligent dilettante” so far. What else?

      Yes, Dr. Campbell doesn’t make the best counter arguments. He does rest on his credentials a bit too often. I probably would too if I had his creds. But as he was willing to have a discussion with Minger, a comparative nobody, it doesn’t seem like he’s insulating himself within an academic barrier. Sure he has a career to defend. Who doesn’t? Although, he already put his career on the line by writing the China Study book. It was a departure from the mainstream; he was going to attract critics. Okay, he’s not a master at public dialog. I don’t expect every scientist to be a gifted debater.

      I was confining this particular criticism to debunking of the China Study research, not Campbell’s book. Whether humans ate meat for how long isn’t a response to the China Project data. As for Campbell’s book—a collection of research he feels offers considerable evidence—you’re right, it needs to be strongly compelling, and I don’t think it is, but that’s just my opinion for what it’s worth. His perhaps tenuous speculation in his book may be a reason to doubt some of his past research, but it’s not very strong reason.

      If I remember correctly, Campbell will acknowledge that his book premise is based on his speculation according to his interpretation of the data he accumulated, not on anything absolute or irrefutable. He wrote a pop book on the subject, he didn’t submit it for peer-review because he understands that it’s conjecture. He feels it’s informed speculation, that conventional nutrition science is leaning his way and is too conservative to budge, but it is still speculation nonetheless.

      People without PhDs or other form of decent credentials can critique whatever they want. They could even be right. But it’s not rational to accepted opinions from every source as if it holds equal weight to everything else even if you like the sound of it. Heck, especially if you like the sound of it! Credentials of some sort matter, but of course, they are not guarantees of perfect sources of information either.

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  6. A critique of Forks Over Knives, well, it’s a little bit outside the scope of this blog as far as I know, none of the authors here has expertise in nutrition.

    But okay, as far as general skepticism goes, it’s fair game, if a little bit too easy. Have your baloney detector fully charged before seeing most any documentary on food and nutrition, because it will be depleted by time you finish the film. Have your baloney detector fully charged before seeing most any documentary for that matter.

    If anyone is telling you they “know” what the optimal diet is, it’s your first clue that you need to be skeptical of everything they say. Best anyone can talk about are associated risk factors.

    Linking to Eatwild.com and Gary Taubes for counter claims is sketchy business. Yes, I realize there are studies on the Eatwild site that I’m supposed to look at, but of course they are going to be cherry-picked to bolster their marketing of grass-fed beef. The website obviously has a bias, it’s no more convincing for me to link to PCRM’s website as a legitimate non-partisan source of information.

    Finishing off your review with the grass-fed beef sales pitch isn’t very compelling skepticism, nor is the alternative diet recap replete with superficial reference to the Masai. Even much of your language on the topic is identical elsewhere. “The medical establishment has, for decades, demonized saturated fat…” Really? Is that sort of objective language useful in accurately describing what happened? Are nutritional guidelines suggesting to reduce dietary saturated fats really the same thing as something being “demonized?”

    It doesn’t seem like good skepticism to counteract potentially fringe claims with opposite fringe claims; combating dietary pet views with dietary pet views. If we really needed a primer on dietary pop-pseudoscience, we could visit one of the zillion alternative health theory blogs or best-selling books on the subject authored by “Joe Health Guru” (Dr. title optional).

    There was absolutely nothing new or unique in this blog post that couldn’t have been gotten elsewhere with cut and paste, and just because the information is “out there” doesn’t mean it’s credible. A solid skeptical approach is lacking here.

    Yeah, Forks Over Knives is propaganda, but we don’t need to resort to even shoddier claims to tell us so.

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    1. The most interesting part of any comment is the person's motivation for leaving it. Do you care to make your bias explicit?

      You write: "Linking to Eatwild.com and Gary Taubes for counter claims is sketchy business." Why? I was simply showing that there is empirical evidence that contradicts the empirical evidence presented by the film's producers. What is one to do when facing two contradicting empirical based claims?

      You also write: "It doesn’t seem like good skepticism to counteract potentially fringe claims with opposite fringe claims; combating dietary pet views with dietary pet views." First, would you mind enlightening me on what exactly constitutes "good skepticism"? Second, I think you missed the point. I'm not advocating any dogmatic dietary pet views and I think I made that explicitly clear. Rather, I'm suggesting that there are any number of healthy diets. In my opinion, when in doubt, eating foods in their natural state (like grass-fed meat) seems like the prudent thing to do.

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    2. Long couple posts ahead, but you asked for some background since you would find it so interesting.

      Ethically – I question the exploitation of animals where there is little need to do so.

      Environmentally – The data are fairly clear that people should be eating less animal products, not more. (http://tinyurl.com/7um9qwu) (Plenty of graphs like those around) I’m unimpressed with the arguments of universal locavorism or a pre-agricultural agriculture. We should work with the system we have, not overhaul civilization. This isn’t an argument for veganism though.

      Health – I question the quest for optimal diet armed with our current knowledge. Follow general guidelines, avoid obvious junk foods, and don’t sweat things. I’m in the Jennifer Michael Hecht camp where I don’t think fretting over dietary perfection for maximum longevity is all that it’s cracked up to be. Like many of her views, I found it comforting. If perhaps my ethical motivations are misguided and it costs some years off of my lifespan, that’s okay, it’s about how I live, not how long. Of course, mainstream nutritional science says I’ll be more or less fine depending on a few plus or minus lifestyle, environmental, and hereditary variables.

      Aesthetics – I question the aesthetics of exploiting animals, the act of slaughter and the implications on humanity’s character in knowingly exploiting the defenseless out of tradition, habit, and whim. Who’s to judge us? No one but ourselves; it’s worse than if there were a God.

      With that said, I tie my hands of three out of four of my stated biases, I won’t advocate for them, because they are not appropriate in this context. Some of my views are after all, extraordinary claims considering the cultural norm. They don’t feel that extraordinary as I go about my life, but I have no delusions that I’m not of fringe thinking on such matters. I share some good company though. I will retain my health bias questionings because dietary faddism runs rampant.

      I confess that I haven’t seen Forks Over Knives so I’m not really here to defend what I haven’t watched. I’ve seen similar documentaries and they are all awful. Still, I’m not being a very good skeptic to dismiss what I haven’t even seen, but I have a decent enough gist of what the movie is all about. I’m not all that supportive of conclusions reached in the China Study book. The China study Project research, I don’t have much qualms with, but its implications are limited. So those are my biases.

      I suppose all of the above still puts me in certain tribe. Fair enough. I’m the same commenter to request that when animal ethics are concerned, to please not to post news about PeTA because as a subject, it offers poor, controversial quality of information where better sources almost always exist. Michael wasn’t really pressing any direct arguments with his casual links, but still, no need to clutter up the place. More signal, less noise please.

      http://tinyurl.com/6wo5m9q
      (I set up a new LiveJournal account, because the AIM one would never post properly, though I don’t really post all that often.)

      My motivation here is similar, the quality of your sources aren’t very good. Your skeptical methodology isn’t very good.

      To be honest, good skepticism is a skill I’m working on, that’s why I’m here. I can’t give you a pat definition, though I can tell you with absolute authority what qualifies as art (kidding).

      If you aren’t sure what good skepticism is, here is a decent podcast

      http://tinyurl.com/6uoa8yd

      Maybe try Bertrand Russell

      1.When the experts are agreed, the opposite opinion cannot be held to be certain.

      2.When they are not agreed, no opinion can be regarded as certain by a non-expert.

      3.When they all hold that no sufficient grounds for a positive opinion exist, the ordinary man would do well to suspend his judgment.

      Okay, I was a bit cheeky, but all the background stuff you requested is out of the way.

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    3. If you don’t understand why linking to a marketing website and a science writer with a fat deal for a controversial book who’s entire premise is that nutritional science is wrong, isn’t grounded in good skeptical practice, I don’t know what to tell you. Ask your fellow Rationally Speaking bloggers how kosher this approach is. If they agree that Eatwild.com and Gary Taubes hold some sort of nutritional expertise, I’m not one to argue further, I will defer to your peers because I’m scratching my head as to why I’m reading this sort of post on this blog. My assumption so far is that they think this is okay, but perhaps they didn’t read your material all that closely. If this blog is going to be the philosophical Huffington Post, where there is no vetting whatsoever, just a kludge of disparate and conflicting approaches, perhaps I’ve misjudged it.

      If your piece was presented in the context of, “Here are some controversial nutritional ideas the Gary Taubes has that I feel may have merit,” Okay. But the point of this post was to combat extraordinary claims; you shouldn’t resort to extraordinary claims to do so. You should stick to established science, not a book with the subtitle “Challenging the conventional wisdom on diet, weight control and disease.” Forks Over Knives is unconventional, so why challenge it with the unconventional? We don’t challenge Intelligent Design with the Aquatic Ape Hypothesis. We challenge it with boring old modern evolutionary synthesis.

      You most certainly are advocating a dietary pet view. Your sources and language are abundantly transparent. If I go to a mainstream dietary food guidelines website from anywhere in the world and read up on their recommendations, I’m pretty sure I won’t find mention of Eatwild.com, Gary Taubes dietary debunking, what the Masai ate for brunch, reminders to take into account “the evolutionary picture,” and deference to naturalist fallacies.

      Oh, that’s right, it’s a world conspiracy suppressing the truth. The whole planet is duped. No amount of credible research can be used to refute any assertions, unless they agree with Gary Taubes (and assorted company) and the nutritional superiority of grass-fed beef. It’s all a big mess like climate science and evolution. In the end, go with your instincts, “I feel better on this diet.” “Doesn’t seem so hot outside to me.“ “I don’t ‘see’ evolution happening, a designer must have done it.” Shows what science really knows, the so-called “experts” are all wrong.

      There are any number of healthy diets? You don’t say. When in doubt eat foods in their natural state? Thanks so much for the diet tips. I’m pretty sure every nutritional guideline on the planet offers such suggestions by focusing on whole foods and limiting or just not including junk foods in their recommendations. There is no reason to bring up Gary Taubes or Eatwild.com if that is the mundane point you were trying to make.

      Besides PCRM, which should rightly be discounted due to its obvious bias, find one dietary guideline from this webpage list that advocates either a Forks Over Knives dietary plan, or Gary Taubes’s low carbohydrate diet purported to prevent all the world’s chronic disease.

      http://tinyurl.com/892u7s8

      Yeah, yeah, it’s Wikipedia, but it’s decent list for a jumping point to most of the government and institution backed dietary guidelines out there. It’s called a consensus.

      The best I can do is cite credible information backed by peer-review expertise. You should try it out and take a few steps away from the pop-health-and-diet-blogosphere.

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    4. First of all, I certainly appreciate the tongue-in-cheek parts of your comments. Well played.

      You are quite the contrarian. It's OK, I have strong contrarian tendencies too, but I try to be aware of it when discussing important matters, like health. Are you sure your contrarianism isn't getting in the way of your pursuit for truth though?

      I'll respond to some of your points from your first comment in what follows.

      Environmentally: That's weird, I don't think the data are clear at all. What about this detailed analysis (from a well respected source) showing that eating meat is better for the environment? Or is this just popular garbage too?

      Health: We probably agree on more here than meets the eye. As I suggested, I don't believe there is one optimal diet either. I, like you, think it's far more important to avoid certain things like junk food.

      Aesthetics/Ethics: As I said, I respect the choice to avoid eating animals for these reasons. If one places a higher value on avoiding animal products for these reasons, that is commendable. I have a problem when people overstep the their bounds though and try to convince people of health benefits that haven't been proven to exist.

      Here are some thoughts from your second comment.

      You write: If you don’t understand why linking to a marketing website and a science writer with a fat deal for a controversial book who’s entire premise is that nutritional science is wrong, isn’t grounded in good skeptical practice, I don’t know what to tell you. Again, as I mentioned in an earlier response, I might take your argument more seriously if you attacked the ideas and not the source. Ever heard of an appeal to authority? If not, I'd recommend looking it up and you might just become a better skeptic yourself (whatever that means).

      My claims are anything but extraordinary. I'm supporting the idea that humans should eat the same foods that they have eaten for a long time. To call this a fad diet or "pet view" is ignorance. But, again, you seem to place more trust in what the experts have to say. You do realize it's possible the guidelines are based on bad science, right?

      You write: "the so-called “experts” are all wrong." That's a nice attempt at mischaracterizing my position. However, I must correct you: I never actually said that. I said some of the experts are wrong in some fields.

      You write: "I’m pretty sure every nutritional guideline on the planet offers such suggestions by focusing on whole foods and limiting or just not including junk foods in their recommendations." Again, I think you're grossly mistaken here. I hate to be a pedant but I don't think you really believe this. Really "every" nutritional guideline?!?! Perhaps we just disagree on what constitutes "junk food".

      You call into question my sources as unreliable and then cite Wikipedia?!? That is just laughable.

      The bottom line is this: I don't necessarily discount a claim because a "pop-health-and-diet" blogger agrees with it.

      If you're interested in truth, you should try taking your contrarian spectacles off sometime.

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    5. I didn’t really offer my background as a debate; it was more a courtesy since you asked.

      I threw in the environmental link for two reasons. My ideas in that context are informed by, I assumed, uncontroversial data, and I figured I’d offer an example link of what I consider a reasonable source. It wasn't vegan propaganda, no mention of vegetarainism, just a graph on food efficiency. I certainly wasn’t expecting the old “vegetarians kill field mice” response to such an innocuous chart. I should’t have put the link up if I wasn’t expecting a response. I’m so very tempted to respond, but it’s too far off topic. Well, it’s certainly a better source than Eatwild.com. I’ll let it rest at that.

      Overall, I’m not presenting disagreement with your ideas nor do I really want to debate meat-eating. I don’t think I’m being contrarian. The opposite really suggesting that conventional consensus be honored. Also, as you’ve said, I haven’t challenged your ideas; I’m haven’t offered an opposing argument. My issues are your sources and your approach.

      Sure there is the danger of appeal to authority or consensus, but sources and credentials matter.

      On good skepticism, just because a crystal definition of something may not exist, doesn’t mean that it has no meaning. All our labels are nebulous, but I most certainly think it is possible to be a good skeptic and there are reasonable guidelines.

      For a good skeptic, it’s essential where we get our information and what information we use to present arguments.

      A website promoting something like a specific food, isn’t a good reference. We shouldn’t provide a link from the dairy counsel as evidence that dairy is healthy. No doubt, they will have plenty of studies demonstrating exactly that. Those studies will be real studies even. But we need a reasonable third-party to weigh all the evidence and offer the relative health pros and cons of dairy consumption.

      My Wikipedia link was a list. There is no analysis or opinion to create controversy. I could have pasted every URL to all the organizations, my first thought, but that seemed tedious. It doesn’t matter whether I believe conventional nutrition standards. My point was that those global, though independently arrived, dietary guidelines are constructed on conventional science and though there is variation, they do have a certain harmony. Admittedly, perhaps I didn’t choose the best delivery to convey my idea.

      If I were going to critique the unconventional assertions of Forks Over Knives, I would start with that global body of knowledge, not a book challenging some perhaps controversial topic within nutrition. Citing Taubes is problematic in this regard. Yes, he is a very strong science writer, a plus, but his premise—not yours, but you’re basing your post on his thesis by referencing him—is that all the experts are wrong.

      You don’t have to discount a claim because a pop-health-and-diet blogger agrees with it, but if you want to convince people, you shouldn’t present such claims as noncontroversial. Give us the credible sources, start with the middle ground, don’t pull from the margins. There is a risk of cherry-picking studies though (like the milk example), and especially with health, there’s plenty of conflicting data, so it’s prudent to rely on credible institutions with the expertise to analyze everything and offer a holistic understanding. Are experts perfect? No, but there’s a conservatism in consensus building that recedes from extremes.

      You said, “My claims are anything but extraordinary. I'm supporting the idea that humans should eat the same foods that they have eaten for a long time.”

      This is an extraordinary claim. On the surface, this seems like common sense, sure. You are obviously steeped in this perspective. But your skeptical audience has no reason to assume its truth. It doesn’t seem all that relevant to the claims that Forks Over Knives is making. And that’s the problem, your post wasn’t really critiquing Forks Over Knives, it was a platform to forward your own personal nutritional views.

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  7. http://rawfoodsos.com/2011/09/22/forks-over-knives-is-the-science-legit-a-review-and-critique/

    That's the best critique on "Forks Over Knives" that you'll find; recommended by Dr. Harriet Hall from the Science-Based Medicine blog.

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    1. A reply from Dr. Campbell himself, author of the China Study, featured in the film, to this blogger's critique of that work.

      http://tynan.com/chinastudyresponse

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  8. "I’m interested in eviscerating the health based reasons for avoiding all animal products that were provided in the movie," so...(sounds like you have your mind made up) of those patients with advanced heart disease Dr. Ess kept alive by switching to a whole foods, plant-based diet, you contend their survival was coincidence? He's established a treat & reverse program for heart disease that is diet based. It works. Yes, small amounts of healthy meats only raise your all cause mortality risk a small amount... so eat as you like, but I do recommend not dismissing the vast amounts of nutritional research done on the relationship between diet and disease.

    Reading all this research is not practical so I recommend someone to interpret it, like Dr. Greger who has a website "nutrionfacts.org" devoted to the dissemination of scientific results relevant to human health and diet (non profit, medical information...) http://nutritionfacts.org/

    I lost two family members, one to heart disease and one to cancer, in my estimation 10-20 years too soon, most likely due to their diets. I've been learning a lot about prevention through diet. A fascinating field of research!

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    1. I'm sorry to hear about your loss :(

      Anyway, you seem to be contending that absolutely the only thing that changed in these patient's diets was the removal of meat. Are you sure about that? If not, how can you be so confident that the meat is the problem?

      If you want to get an alternative perspective I'd recommend reading Gary Taubes book Good Calories, Bad Calories.

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    2. No, I'm not sure that the removal of meat was the key to their survival. The diet is amazingly low in fats of all kinds, even plant fats, and of course is totally free of processed grains, flour, junk foods etc. Seems to me that given (1) our interest in own well-being and (2) our scientific skills, we should have figured out an optimal human diet by now. Even the most well-informed nutritional scientists don't agree on what the data mean... Although I like Pollan's advice "Eat Food. Not too much. Mostly Plants."

      Maybe we need to wait a few more centuries.

      ps - I briefly checked out Taubes book & seems to me to be aimed at dealing with obesity. I'm not interested in the obesity problem. I'm more interested in how non-obese people acquire diet-related diseases. I recommend that nutrionfacts site for this.

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    3. Taubes' book is about more than just obesity, but it is a lengthy read and much of it is about obesity.

      Anyway, I think Pollan's heuristic is very helpful if we understand what those terms used in it actually mean.

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    4. It appears that Taubes later authored a shorter read, which Dr. Harriet Hall reviewed last year on Science-Based Medicine. (Looks to me like another example of the low-carb fad.)

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  9. http://www.youtube.com/watch?v=6-0FFC7AcUQ
    The Masai DID get heart disease from their high animal product intake.

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    1. your using durianrider as a counter argument. please.

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  10. First question:
    " I got the impression that the authors used science to promote their pet views"

    "Pet Views" -- was that intentional? :-) [meowwww!]

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  11. Dear Mr. Linster, did you write this line, “The most beautiful aphorism has yet to be written,” and if so, why?

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