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What Can We Learn from the Kitavans?

A Swedish researcher, Staffan Lindeberg, has been studying the inhabitants of Kitava, one of the Trobriand Islands of Papua New Guinea. He claims that sudden cardiac death, stroke, and exertion-related chest pain never occur in Kitava; and he attributes this to their eating a Paleolithic diet.

2,250 people live on Kitava. They are traditional farmers. Their dietary staples are tubers (yam, sweet potato and taro), fruit, fish, and coconut. They don’t use dairy products, alcohol, coffee, or tea. Their intake of oils, margarine, cereals, and sugar is negligible. Western foods constitute less than 1% of their diet. Their activity level is only slightly higher than in Western populations. 80% of them smoke daily and an unspecified number of them chew betel. The macronutrient composition of the Kitavan diet was estimated as 21% of total calories from fat, 17% from saturated fat, 10% from protein, and 69% from carbohydrates.

Lindeberg’s Kitava study examined a sample of 220 Kitavans aged 14-87 and compared them to healthy Swedish populations. They found substantially lower diastolic blood pressure, body mass index, and triceps skinfold thickness in the Kitavans. Systolic blood pressure was lower in Kitava than in Sweden for men over 20 and women over 60. Total cholesterol, LDL cholesterol, and apolipoprotein B were lower in men over 40 and in women over 60. Triglycerides were higher in Kitavans aged 20-39 than in Swedes of the same age. HDL was not significantly different.

Another study examined how the Kitavans’ risk factors changed with age.

I am always suspicious of initial reports of unusually healthy or long-lived groups in remote areas, because I have so often seen such reports disconfirmed by subsequent investigations. Lindeberg’s studies were done in the early 90’s and have not been confirmed by other studies in the ensuing two decades. In the Kitava study, the ages of subjects were not objectively verifiable, but were estimated from whether or not they remembered significant historical events. The absence of heart disease and stroke was deduced by asking islanders if they had never known anyone who had the symptoms of either condition. This was reinforced by anecdotal reports from doctors who said that they didn’t see those diseases in islanders. EKGs were done on the Kitavans, but a normal EKG does not rule out atherosclerosis or cardiovascular disease. I’m not convinced that we have enough solid data to rule out the presence of cardiovascular disease or other so-called “diseases of civilization” in that population.

But even supposing those diseases don’t exist in Kitava, what could we deduce from that? Lindeberg thinks it constitutes evidence to support the Paleolithic diet of meat, fish, vegetables, fruit and nuts that our ancestors ate 2,000,000 to 10,000 years BP. We aren’t really sure what our Paleolithic ancestors ate, but we can be reasonably sure they didn’t typically eat what Kitavans eat. The Paleolithic diet included meat and was probably much higher in protein than the Kitavan diet. Most of our Paleolithic ancestors probably did not have access to coconuts or taro or to an abundance of fish. Our ancestors were hunter-gatherers, while the Kitavans are farmers; agriculture did not develop until around 10,000 BP.

I don’t see how we could assume the absence of those diseases was due to the Kitavan diet. Other causes would have to be ruled out, including heredity and environmental factors. Even if it was due to the diet, how could we possibly know whether it was due to the diet as a whole or to some specific aspect or component of the diet?

What can we conclude?

The Kitava study serves as a disconfirming example to discredit the claims made for low-carb diets. Kitavans eat a very high-carb diet, with lots of saturated fat and little protein, and they appear to thrive on it without becoming obese or developing a high incidence of metabolic syndrome as the low-carb theorists would predict.

It is evidence against the hypothesis that low-fat diet recommendations caused the obesity “epidemic” simply because people replaced fat with carbohydrates. It shows that a diet high in carbohydrates does not necessarily lead to obesity, especially if they are complex carbohydrates and the total calorie intake is not excessive.

It supports the general consensus of most diet experts that a predominately plant-based diet is healthy. It supports Mom’s admonishments to eat our vegetables.

It suggests that saturated fat need not be avoided, especially if it is of vegetable rather than animal origin.

It tends to confirm the health benefits of weight control and the principle that weight can be controlled simply by limiting calories. The Kitavans are not overweight, and their intake of calories is lower than the conventional Western diet.

It tends to support advice to avoid processed foods and refined carbohydrates.

It reinforces the concept that humans can thrive on a wide variety of diets.

Bottom line

The Kitava Study provides food for thought; it doesn’t provide enough justification to recommend either a Kitavan diet or a standard “Paleolithic diet” over other healthy diets.

Posted in: Nutrition

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87 thoughts on “What Can We Learn from the Kitavans?

  1. Pharmacist-in-Exile says:

    Interesting to see a discussion of these oldish pieces from Lindeberg’s paleodiet research from a non-Swedish source. He has recently been active in the major Swedish newspapers in a very pseudoscientific discussion about diet – primarily a war between LCHF, 5:2 and balanced calorie restriction – purporting his “evolutionary consequences”. How come you chose the topic Harriet – or do you have Swedish connections?

    1. Harriet Hall says:

      Why did I choose this topic? Because a reader asked me about it.

      1. Pharmacist-in-Exile says:

        A reason as good as any! Thanks for sensible writings.

  2. Another great article Dr. Hall. I would also wonder what their infant mortality rate is, life expectancy etc. I work in community health and know there are more factors to mortality and morbidity than just diet. As you said their are environmental factors to take into consideration. But of course the intention of this study was not discover, but to confirm what they already believed. Which as we know is not science. As the dietician tells our patients. “It is simple math. Calories in, calories out.” I would guess that the proponents of these paleolithic fad diets do not appreciate the suggestion that their philosophy is not the panacea they claim.

  3. stuastro says:

    I may be incorrect but I am sure that some months or more ago I read a piece on SBM which stated that it didn’t much matter where your calories came from, just as long as you consumed the right number of calories. Or did I get that wrong?

    1. Bobby Hannum says:

      I’m can’t comment on that piece you read, but usually that sentiment is limited specifically to weight loss, rather than general health. You *could* eat only Twinkies, and as long as you’re not getting too many calories you’ll lose weight. In fact, there was a researcher who did just that (to himself). But that isn’t the healthiest thing you can do.

      1. Ken Hamer says:

        I remember seeing this as well. Apparently the researcher went on a junk food diet to see if he could reduce weight by reducing calorie intake. While he expected other bad health outcoumes (i.e. blood sugar), it turns out that almost all diet metrics improved.

        Not certain but it might have been Aaron Carroll at http://theincidentaleconomist.com/

    2. Harriet Hall says:

      It does matter where your calories come from. We need fats, carbs and protein in our diet, and we need essential vitamins and minerals and a variety of amino acids. We haven’t established what percentage of fat, carb and protein is ideal, but we know people can thrive on diets with a variety of percentages. We have established that if you take in fewer total calories than you expend, you will lose weight.

  4. Carl says:

    Just glancing at this page…
    http://www.staffanlindeberg.com/TheKitavaStudy.html

    …I noticed that they say 6% of Kativa’s population is age 60-90, while a quick Google tells me the US is 12.8% age 65+.

    It also says, “The elderly residents of Kitava generally remain quite active up until the very end, when they begin to suffer fatigue for a few days and then die from what appears to be an infection or some type of rapid degeneration.”

    So they work until they drop, and they might not die of heart disease but they die of infections. And for that they have to give up pizza and cheeseburgers?

  5. WilliamLawrenceUtridge says:

    I would also be curious to know the life expectancy of Kitavans. Do all those positive biomarkers translate into longer lifespans? And would the extra lifespan be worth giving up broadband…

  6. windriven says:

    “I don’t see how we could assume the absence of those diseases was due to the Kitavan diet. Other causes would have to be ruled out, including heredity and environmental factors. Even if it was due to the diet, how could we possibly know whether it was due to the diet as a whole or to some specific aspect or component of the diet?”

    Amen. And suppose for a moment that we could somehow determine that diet was principally responsible. The Kitavan people have apparently lived in a relatively closed genetic pool for some time. Standard evolutionary theory would suggest that genomes that thrived on the available diet would have a reproductive advantage over those that didn’t. Would those of Aleut ancestry be expected to thrive on a Kitavan diet? No? So why would anyone think that porting the Kitavan diet to western Europeans or sub-Saharan Africans or Tibetans would necessarily ‘spread the wealth’?

  7. angorarabbit says:

    “The macronutrient composition of the Kitavan diet was estimated as 21% of total calories from fat, 17% from saturated fat, 10% from protein, and 69% from carbohydrates.”

    I don’t know whether to laugh or cry. This is neither a western nor a paleolithic diet. This is closer to what we’d love westerners to consume. Typical western diet is 31-32% calories from fat, 14-18% from protein, 3% alcohol, and balance from carbohydrate. Kitavan diet is closer to current recommendations of <30% fat calories, 10-12% protein, and balance complex carbs. At 21% of fat calories, I don't particularly care what % of fat is sat/unsat except for getting sufficient essential FAs, which they do from fish.

    I also don't buy Lindeberg's claim that, although the Kitavans are traditional farmers, their energy expenditure is "not much more than westerners." That's not possible. Activity levels in the 1990s are notoriously inaccurate; measurements were fraught with error. Current technologies are vastly improved.

    1. duggansc says:

      You know, it wasn’t until I read your quote that I realized that the Kitavans are apparently eating 117% of their total calories, quite a trick. :)

      1. Harriet Hall says:

        The 17% saturated fat is part of the 21% total fat, so they’re only eating 100% of their calories.

        1. duggansc says:

          Ah. That makes more sense. I was parsing your sentence incorrectly, one of those issues with how we do nested lists in English. Thank you for the clarification, Dr. Hall.

    2. john says:

      It sure sounds like a variant of what the paleo diet ‘experts’ would (rightly, wrongly or neutrally) currently recommend.

      Not sure what part you think isn’t,,,? I’m guessing you may equate paleo to a sub set of the low carb diets, it hasn’t been like that for a good while so far as i can tell from the current popular gurus.

  8. HH mentions this, but it should be emphasized that, “what our ancestors ate” covers a long period of time, and a lot of foodstuffs. If you limit it to the paleolithic (as these people so often do for reasons unknown to me as this archaeological designation has little to do with diet), there is still a large variety of diets to consider, and a lot of other factors.

    Anthropologists use the reverse of the term h-g, that is–gatherer-hunter. Most populations were primarily dependent on nuts, seeds, roots and berries. Hunting was not consistently successful and often was not the primary source of protein–although it did seem to make a critical difference in brain development.

    http://hells-ditch.com/2012/08/archaeologists-officially-declare-collective-sigh-over-paleo-diet/

    See this great piece for a science-based discussion which says it better than my 30 year old Anthropology degree enables me to do.

  9. rork says:

    I have seen 2D gels of plasma from people from the island, and recall we saw some apo-lipoprotein variants that we had never seen in Europeans, and homozygous in every person. Trouble is I can bring that 25-year old data up, and I can’t recall which gene for sure, but I’m thinking it was APOA1 (a giant spot on the gels). I’m not saying it is the cause of anything, I just remember wanting to study it and not having time. At first we thought something was screwed up with the samples.
    We were studying APOE allele affects on lipid levels, and it mattered.
    We were blithely unaware of any Alzheimer’s effects. I’m e3/e3 at APOE (I’ve given blood to labs about 100 times by now). Boring can be OK sometimes.

  10. stanmrak says:

    What we can learn is that it’s best to eat whole, unprocessed foods. Except that’s already obvious isn’t it? Any ‘food product’ that comes in a package with a list of ingredients has more chemicals and additives than you would ever believe, (unless it’s certified organic) and many are not even thoroughly tested by anyone but the manufacturer. Last time I checked, we had passed 15,000 different approved additives. These are also not listed on the label. Some of them are known carcinogens… sodium nitrate comes to mind initially. In addition, any chemical used in the processing stage is also not revealed. McDonald’s french fries are not addictive because of their taste – it’s the chemicals.

    1. windriven says:

      “What we can learn is that it’s best to eat whole”

      You eat watermelon rind and pecan husks?

      “unprocessed foods.”

      You don’t cook your food? You don’t eat smoked salmon or lox or bread or, horror of horrors, bacon?

      “Except that’s already obvious isn’t it?”

      Not to me. I eat a wholesome Mediterranean style diet including olive oil (processed), bread and pasta (processed), seafood (often cooked, pickled, salted or otherwise processed), vegetables (often processed) and fruits (mostly whole. You win on that one). And cheese. Lots of cheese. And cheese is …. processed.

      “Any ‘food product’ that comes in a package with a list of ingredients has more chemicals and additives than you would ever believe, (unless it’s certified organic) and many are not even thoroughly tested by anyone but the manufacturer.”

      Don’t be idiotic. There is a huge range between unprocessed and the sort of artificial, imitation, food-like substances you’re yammering about. No one here is suggesting a Diet Coke and Velveta diet.

      “McDonald’s french fries are not addictive because of their taste – it’s the chemicals”

      Again, who here is advocating the Big Mac and Fries diet? But I’d also note that by the time the fry hits your fry-hole the alleged Gilbert Chemistry set is part of the taste which some, for reasons that elude me, find addictive. Or are you alleging that McDonald’s is spiking their fries with cocaine or something?

      You’re a one trick pony, stan. Its tiresome. Have a thought of your own sometime. You sound like Michael Moore’s Mini Me. Speaking of which …

      1. john says:

        windriven, I suspect stanmrak really means minimally processed foods not unprocessed foods. We can all acknowledge that while both are ‘processed’ there is something of a difference between a home smoked, wild caught piece of salmon and a big mac.

        A more nuanced argument could probably have been made by stanmrak and many of these paleo zealots, but that basic philosophy of eating foods that have been cooked or prepared in a manner reasonably consistent (given modern lifestyles and available foods) to traditional and/or ancient cultures certainly has a strong romantic appeal and seems a good starting point for developing new nutritional hypotheses.

    2. WilliamLawrenceUtridge says:

      Why is certified organic an advantage? Unless you like bacterial infections.

      What’s wrong with additives? They extend shelf life and prevent food poisoning. Do you have some sort of emetic fetish? Do you dislike the delicious flavour and bacteria-free nature of pepperoni? Or fermented sausages, a form of curing and flavouring that is centuries old, harkening back to the good ol’ days of yore when people died too young of infectious diseases for the cancer to chew through their guts? It’s not like additives are selected at random, they have specific effects and are tested for safety; so long as you don’t drink them by the gallon or sprinkle them on your food like salt – there’s really no issue. I mean, do you worry about mint? It’s primary constituent of human interest, menthol, is toxic in sufficient doses. Do you like fiddleheads? What about the cancer risk? Spinach? Oxalates and kidney stones. Surely any fair-minded individual assessing the absolute risks of all these options would concede that the risks of food additives are no worse than certain foods.

      But that’s not you Stan! Stay crazy!

  11. Hello Dr. Hall,

    Dr. Lindeberg’s observations on Kitava are consistent with a wide variety of other studies, some of them detailed cardiovascular autopsy studies, demonstrating that the age-adjusted prevalence of atherosclerosis and myocardial infarction are remarkably low in traditionally-living populations in Melanesia, Africa, and Asia. Melanesians are not genetically protected because when they adopt the ‘Western’ diet/lifestyle, they develop a high prevalence of obesity, metabolic disease, and cardiovascular disease.

    http://www.ncbi.nlm.nih.gov/pubmed/14103185
    http://www.ncbi.nlm.nih.gov/pubmed/5406469

    Although there are no autopsy studies of Kitavans, there is no remaining doubt that certain genetically related Melanesian populations, as well as Africans, are remarkably protected from CVD when they live a traditional lifestyle. Furthermore, Kitavans rarely develop hypertension, which one would expect to see if advanced atherosclerosis were common. We don’t know exactly why these populations are protected, and why they develop disease after diet and (to a lesser extent) lifestyle transitions, but I would be shocked if it had nothing to do with diet. Lifelong leanness is probably a major factor, and also heavy smoking, although most Kitavans are light smokers.

    The Lee et al. study I cited above is particularly interesting because it represents thousands of cardiac autopsies from Africa, Asia, and the United States (including African-Americans and Asian-Americans). None of the populations consume a “Paleo” diet, but some of the traditionally-living groups have age-adjusted myocardial infarction prevalences that are below the detection threshold. I’m happy to provide you with a PDF if you e-mail me at wholehealthsource at yahoo dot com. Cheers.

    1. Harriet Hall says:

      “I would be shocked if it had nothing to do with diet”
      I would too. The question is “what” it has to do with diet. And if the Kitavan “secret” differs substantially from the advice we already are getting from experts about healthy eating and lifestyle.

      1. Personally I think the “secret” to Kitavan health overlaps substantially with conventional dietary advice to eat minimally refined foods, exercise, avoid sweetened beverages, and avoid smoking (at least heavy smoking).

        But as you said in your article, it’s not consistent with advice to avoid diets rich in high-glycemic carbohydrate and avoid saturated fat. Their diet has a very high glycemic load. Of course, it’s hard to attribute specific health outcomes to specific dietary elements in this case, but at least we know these dietary patterns can be consistent with leanness and cardiometabolic health in some contexts.

        I think their avoidance of flour-based foods is interesting. Flour-based foods (particularly refined flour) are calorie-dense, not very satiating per kcal, and lend themselves to highly palatable baked goods that are often emulsified mixtures of starch, fat, and/or sugar. Kitavans get the majority of their kcals from foods that are lower in calorie density and more satiating per kcal than flour-based foods, e.g. breadfruit, taro, cassava, yam, and sweet potato. These are simply prepared in an earth oven, which is a cross between steaming and baking. It’s hard to overeat plain starches, which form the majority of their diet.

        Their food environment and eating patterns probably matter. They eat meals twice per day and the main available snack is raw fruit. There are no calorie-dense processed foods strewn about their daily environment. No food cues from ads. No drive-throughs. Preparing food requires effort, and the resulting dishes are generally simple– not an invitation to overconsume. Regular physical activity is certainly a factor, and perhaps also circadian factors related to sufficient sleep and synchronization with the day-night cycle.

        Personally, I think the main take-away points from this study, in the context of other similar studies, are: 1) it is possible for human populations to have a surprisingly low prevalence of obesity, metabolic disease, and ischemic heart disease, and 2) the study of metabolically healthy non-industrialized cultures may provide clues on how to live better today, and provide a sort of “evolutionary template” for generating hypotheses about the pathogenesis of human illnesses that have accelerated since industrialization.

        I think Dr. Lindeberg’s work on Kitava has been valuable because he’s one of the few researchers who has applied modern biomedical methods to the study of non-industrial cultures. His controlled diet trials with the “Paleolithic” diet are also interesting.

        1. windriven says:

          “it is possible for human populations to have a surprisingly low prevalence of obesity, metabolic disease, and ischemic heart disease”

          Sure. I don’t think anyone would argue that a diet of brown rice and minimally processed fruits and vegetables coupled with regular exercise would lead to positive health outcomes.

          But speaking only for myself, my goal in life is not to simply maximize the number of days that I get to see the sun come up. I love a perfect pear. I also love a nice pear galette. And finishing up with a few cl of Clear Creek* pear brandy is pretty nice.

          Again, from at least my perspective, there is room in a life well lived for a diverse diet consumed in moderation including even the occasional french fry (mmm, salt, grease and starch, the three basic food groups). If that costs me a few months … well, I was never going to live forever anyway. But eating an unending diet of yams and manioc would certainly make it feel like forever :-(

          *Forgive the shameless promotion of a local PNW product. Clear Creek Distillery, located near Mt. Hood, produces fabulous fruit spirits including a pear brandy that tastes like a crisp fall afternoon.

          1. Alia says:

            This pretty much sums up my attitude to diet, too. I try to eat a healthy, balanced diet that includes all necessary nutrients and is not too caloric, but my life without some chocolate and icecream would be miserable. And then there are all those beers from small breweries that one wants to try…

            Well, it also helps to have good genes. My father is 80 now and in great health (well, apart from cataract). He’s never eaten any special diet but he still cannot imagine a day without a walk that is at least an hour long. So that probably helps, too.

  12. calliarcale says:

    “The Paleolithic diet included meat and was probably much higher in protein than the Kitavan diet.”

    The problem with this as others have noted is that there really is no such thing as a Paleolithic diet. It varied with region. Hunter gatherers in Papua New Guinea would not eat the same things as hunter gatherers in the Ituri rainforest of Africa or hunter gatherers in Greenland or hunter gatherers in Mexico. Our common pop culture image of a Stone Age person is a hairy European dressed in skins and living in caves, but of course only the European ones were like that, and even they varied tremendously — a Stone Age costal Italian would have a different diet than, for instance, Oetzi, the “iceman” found in the Alps.

    So anytime someone says anything about the merits of “the Paleolithic diet” you can pretty much assume they haven’t put a lot of thought into what they’re saying, or they would have realized this.

    1. Garett says:

      “So anytime someone says anything about the merits of “the Paleolithic diet” you can pretty much assume they haven’t put a lot of thought into what they’re saying, or they would have realized this.”

      Really? Because I eat what would be considered “Paleo” and I’ve put in a considerable amount of time, effort, and thought into it.

      I don’t eat like this because I’m trying to mimic a single diet – I’m eating like this because it makes bloody sense. It’s a nutrient dense diet and as such I avoid grains because they are nutritional junk. I think to your point, however, the name is terrible and it’s unfortunate. Also, the “eat this way because of evolution” is somewhat misleading. Matt Lalonde does a good job of summing this up: http://vimeo.com/27570335

      1. windriven says:

        “Because I eat what would be considered “Paleo” and I’ve put in a considerable amount of time, effort, and thought into it.”

        By whom? calliarcale’s point is that paleolithic diets were geographically diverse. Those who bandy about ‘paleo’ diets don’t seem to be thinking through just what that means.

        1. Garett says:

          There’s an entire community of people that simply identify with the term “Paleo” as a template for eating a nutrient dense diet. So when I say I eat “Paleo” I follow what the “Paleo” community has identified as a pretty good template.

          My point was to agree that the “Paleo” term is a misnomer, but if you look at the actual content of the diet it’s sound. So when I say, the “Paleo” diet is a good diet, I’m not saying that because of the evolutionary argument. I’m saying that because the principles advocated are nutritionally sound.

          SImilarly, if you looked at the content of all geographically diverse paleolithic diets, they all have common elements of being nutrient dense.

        2. Garett says:

          Here’s a great rebuttal to the “there was no single Paleo diet” argument a la the infamous TED talk.

          http://robbwolf.com/2013/04/04/debunking-paleo-diet-wolfs-eye-view/

          1. WilliamLawrenceUtridge says:

            The key and relevant portion though:

            True, and this has again been addressed by Prof. Cordain. Seasonality, locality, variability has ALWAYS been part of this discussion. This is an interesting refrain that was part of the US News critique of paleo, and just never seems to die. Perhaps it’s because none of these folks are actually reading books/papers on the topic?

            Seems to rather miss the point, as Dr. Warinner’s point was that there can’t ever be a single paleo diet. If you assume there is one single diet that is optimal for human health, of all humans, it must have developed in Africa and the “paleo diet” should focus solely on African foods (which even then presents problems as Africa is a pretty big, diverse place, you would probably have to localize it to wherever that population bottleneck of 1,000 people existed 70-100K years ago). Once humans moved out of Africa, you would have to assume each group evolved further in each location – thus there is no one “paleo” diet, there is one per “race”, itself a spurious concept.

            And if you say “the paleo diet is just eating nutrient dense foods” or even “the paleo diet is just eating seasonal, local, variable foods”, you aren’t really adding anything of note to the conversation about diets since that’s pretty much the mainstream recommendation (as even foods flown in are in season and local somewhere). Not to mention, I don’t believe paleolithic people in the arctic regions had canning, or current paleo enthusiasts hunt and eat solely winter-lean deer, mammoths or rabbits. The entire concept, misnomer or not, just seems so absurd. Humans can survive and even thrive on nearly any diet that meets our calorie and nutrient needs – and that includes eating nothing but McDonalds (though to meet your nutrient targets without way over-reaching your calories, you’d need a vitamin or one hell of an exercise program).

            I’ve yet to see any convincing argument that there’s a magical human diet that is optimal beyond some very broad guidelines. Calories in-calories out always wins.

  13. Rob says:

    Just because our ancestors ate that way, does it make it better? Sure, our ancestors survived long enough to reproduce, but how many of their associates died younger, even on the same diet? And, even our ancestors, did not necessarily have long lives. So, how can we state that any type of supposed ancestral diet is superior to our modern version of a healthy diet?

    1. Garett says:

      Because they didn’t from their diet – they died from trauma and infant mortality.

      1. Young CC Prof says:

        Absolutely, people dying of chronic disease is a luxury of modern times, and our ancestors rarely lived long enough to worry about heart disease, cancer, etc. Of course, despite their “naturally healthy diet,” they sometimes died of malnutrition due to limited availability of food, either in variety or in absolute quantity.

        My take on the “natural way” is this: It’s worth figuring out how ancient humans ate and lived, both on the savannah half a million years ago and more recently in other parts of the planet. Then, we can start taking it apart and seeing what aspects of their lifestyle were worth emulating and which were actually harmful to them.

        It is clear that humans are pretty flexible nutritionally and there are multiple possible diets that produce reasonably healthy people. Personally, I don’t believe there is such a thing as the perfect diet, just a range of diets that are good enough.

  14. Jo says:

    > It suggests that saturated fat need not be avoided, especially if it is of vegetable rather than animal origin.

    I’m curious about this statement. I know that it’s just a tentative epidemiological conclusion here, but I’ve heard it claimed before elsewhere and always have had trouble with it: a priori, what in the world could be the chemical difference between plant and animal saturated fat? Are other chemicals possibly dissolved in the fat (e.g., cholesterols and omega fatty acids) being included here?

    1. opicazor says:

      This was one of the inaccuracies in Dr. Hall article I was going to mention. The difference is not animal vs vegetable saturated fat. Most of the sat fat content in kitavan diet comes from coconut consumption, which is mainly MCTs. If we want to be precise, we need to define exactly the kind of fatty acids consumed, not just saying animal vs vegetable, because there are big differences regarding metabolism between MCTs and longer chain SF.

      On the other hand, and athough Stephan Guyenet has already covered most of the points, I would like to indicate that there is a misunderstanding in the article about the so called “paleolithic diet” (a term I dislike anyway). The focus is most about what you avoid eating, than about what you eat. The starting hypothesis is that this kind of diet, is one to which we are better adapted than a diet full of western processed food with high amounts of refined flour, sugars and fats. This hypothesis should be tested in human trials, to be confirmed. On the other hand, I do expect nutrigenomics and nutrigenetics will shed some light on whether or not this broad hypothesis was correct. For sure there will be groups of people or populations, adapted to milk or certain cereal consumption, but the hypothesis and framework is just that. And I think it is a more sound and reasonable starting point, than the current dietary recommendations based on epidemiology and not thoroughly tested on clinical trials yet. If you analyse the bibliography thoroughly, you could find the same level of evidence to back up recommending a western diet or a “paleo” diet, as there is need for further human trials and clear genetic and biochemical explanations of the mechanisms involved.

      Other issue in Dr. Hall’s article is the focus on macronutrient intake that appears through the test. Certainly, the Kitavan diet is an example ruling out the need for a low carb diet. Many people in the “paleo” movement are low carb advocates, but that does not mean the latest research in evolutionary medicine is backing up that approach, except for some short term interventions or certain pathologies. Macros are not the key, but food quality.

      Another area not mentioned and related to western vs non-western eating patterns, is gut flora, and is related to what Dr. Guyenet mentioned on refined flours and sugars. Gut flora research is exploding and I think is the missing link we needed to explain many outcomes found in observational research that could not be rationalized. For example, the beneficial effects of resistant starch due to it’s influence on gut phyla and permeability.

      There is much more to the “paleo” thing, than just the superficial caveman diet recreation and just the evolutionary argument, as everytime more and more evidence is piling up, sometimes in an indirect manner, supporting the hypothesis. I think it is worth exploring and studying with an open mind, as the conventional dietary advice has soundly failed. Why not confirming it or ruling it out?

      Fortunately, I expect, as I said, nutrigenomics and genetics will turn around nutritional research in the coming years, and we will not need to rely anymore on epidemiology (as good clinical trials are so scarce…).

    2. Pharmacist-in-Exile says:

      Fats are tri-esters of glycerol and fatty acids (triglycerides). The fatty acids (of which hundreds have been described) can be grouped according to a number of chemical features, such as containing unsaturations or not, the number and localisation of unsaturated bonds, the number of carbon atoms in the chain, and “exotic” modifications. The following are but examples. Animal fats usually have at least 38% saturated fatty acids and commercial vegetable fats usually less than 25%. Exceptions include coconut fat which is a vegetable fat with around 80-90% saturated fatty acids. There is a differences in composition where solid animal fats have a propensity for palmitic and stearic acids (C16 and C18) while coconut fat is rich in caprylic and capric acids (C8 and C10). And so forth…

  15. Richard Mjödstånka says:

    @Stephan Guyenet,

    here’s a piece of evolutionary rationality for you (or the lack of it thereof):

    In the 1920s, it was observed that the nomadic pastoralists of the Kirghiz and Dzungarian Steppes in Central Asia and northern China subsisted almost exclusively on enormous amounts of fermented mare’s milk and meat from pasture raised animals. Kuczynski did not only report a high rate of obesity, but also high rates of premature extensive atherosclerosis, contracted kidney, apoplexy, arcus senilis, and gout. These pastoralists were often observed to suffer from complications related to cardiovascular disease even in their early thirties. In contrast, their urban counterparts who based their diet on soup, bread, pickles, and potatoes with very little meat were observed to be slim, free of cardiovascular disease and had very good health, even into their seventies when they were still sexually active.

    It was observed that in the 1960s the rates of coronary heart disease of the nomads from Xinjiang in northern China who largely subsisted on pasture raised animal foods was more than 7 times higher than that of other populations both within Xinjiang and throughout China which had a much lower intake of animal fat. These findings from non-industrialized populations in Asia are compatible with the observations of a high rate of cardiovascular disease among the Inuit populations whose staple is marine animals.In 1940, based on years of clinical practice and reviewing medical reports, Bertelsen, who is considered the father of Greenland epidemiology stated in regards to the mortality patterns among the Greenland Inuit that:

    “…arteriosclerosis and degeneration of the myocardium are quite common conditions among the Inuit, in particular considering the low mean age of the population”

    There had been a considerable amount of research carried out in regards to flour-based diet and the health of populations within the greater Asia region that consumed a semi-vegetarian diet based largely on wheat. Examples include the Arab Bedouins and Yemenite Jews, both of which traditionally consumed on average more than 500 grams of bread per day. These populations are known for their exceptionally low rates of coronary heart disease and obesity when following their traditional wheat based diet. Perhaps the largest consumers of wheat that there is considerable data available for are the Bedouins from southern Israel. The great majority of the dietary intake of the traditional Bedouins comes from wheat, typically in the form of full-grain bread, which is especially the case for the poor who eat very little else. It was estimated that the Bedouins traditionally consumed on average 750 gm, or the equivalent of 25 slices of full-grain bread per day.

    The traditional Bedouins had many dietary traits besides an extremely high intake of whole-grain wheat that are considered by advocates of Low-Carb and Paleo diets as being primary causes of obesity and the so-called ‘diseases of civilization’, including diabetes and coronary heart disease. For example sugar intake was observed to be modestly high, a trait comparable to that of the populations in Colombia, Cuba and Venezuela who have traditionally had among the highest rates of per capita sugar consumption in the world and low rates of coronary heart disease mortality. It was estimated that dietary cholesterol intake was only 53 mg/day and saturated fat was less than 3% of caloric intake, suggesting that animal foods as a whole contributed very little to the Bedouins diet. Meat was consumed only about once per month, and virtually never eaten by the poor. Similarly egg and especially fish intake was very infrequent, although animal milk is frequently consumed. Fat intake only contributed to about 11% of total caloric intake, with a relatively low intake of omega-3 fat and a high ratio of omega-6/omega-3 fat. Vitamin A intake was very low, and for the many women who virtually never exposed their skin outside, blood concentrations of vitamin D would have likely been on the low side.

    It has been documented that diabetes and heart attacks were all but entirely absent in the traditional living Bedouins which had an average serum cholesterol of 4 mmol/l (155 mg/dl), and that the great majority of the population were exceptionally lean by western standards, both in terms of weight and skin thickness.The rates of inflammatory bowel disease were also considered to be very low. The few Bedouins that were observed to be obese were exclusively the wealthier elderly who rarely even walked. Being a semi-nomadic population that largely relied on walking as a means of transport, exercise has been suggested as one explanation for their exceptional low rates of obesity. However, many of the women were forced to stay inside their tents all day allowing for little exercise, yet these women with almost no exceptions were slim and free of vascular disease.

    For sources, see HealthyLongevity’s blog post:
    http://healthylongevity.blogspot.fi/2013/08/asian-paradox-low-carb-diets.html

    1. Richard Mjödstånka says:

      Moreover,

      it is hard to justify the notion of low body weight being protective against CHD mortality as such. After the 10-year follow-up of the seven country study, Keys reported that the highest CHD mortality was observed in the Eastern Finnish cohort which consisted mostly of lean, hard working timbermen. In fact, the american scholars was astonished by the high degree of the physical fitness they saw in Eastern Finland. These men had barely never drank soda’s or visited the McDonald’s. Instead, they showed cultural affinity with a diet very high in butter and whole-milk.

      1. Mie says:

        Hard-working woodcutters dying of CHD – as simple as that? Err, how about cigarette smoking, blood pressure issues due to excessive sue of salt etc. etc.? Physical witness is indeed protective against CHD (think of e.g. the condition of the endothelium), but not when a multitude of risk factors cluster against its benefits.

        1. Richard Mjödstånka says:

          The data of the 7CS showed that blood pressure of the Japanese was on par with Europe and cigarette consumption was even higher. CHD was very low on Japanese people at the time (cumulative exposure of low fat diet induced low serum cholesterol concentrations throughout the life).

          The hardworking timbermen in Eastern Finland had staggering cholesterol levels thanks to very high butter fat diet.

          1. the Finnish authorities have mandated selenium be added to crops since early 90s as selenium deficiency was supposed to be a CVD factor. Also, Scandinavian soils can be unusually high in iron. Low vitamin D, and mercury in fresh water fish, are other risk factors for CVD in this population. Hard work in cold weather requires large caloric turnover long-term, which can shorten life expectancy (as with top professional athletes).

    2. Garett says:

      This is *super* interesting. Thanks for sharing. I’ll check out the blog, but I’m interested in learning about these Bedouins too. Do you have any other sources that talk about them? I’m very curious to see what explanations there are for why the women would still be so health despite lack of sun, exercise, etc.

      1. Richard Mjödstånka says:

        ^You can find more information on Beduins from the links I provided.

        Although, the Beduins had vitamin & mineral deficiencies, they managed to keep chronic disease at bay. The Beduins were systematically researched by the legendary diet-heart pioneer J.J Groen. This is standard material, but the Paleo people are so keen on their own “evolutionary rationale” that they do not bother to learn the foundations, the back-bone research to diet-heart.

        I think John McDougall’s MD concept, the “Starch solution” is brilliant. It really brings our attention to the foundations; all healthy & trim populations throughout the verified human history have lived on a starch based diets. Be it native Javanese in South-East Asia, the Central-Africans, the Beduins, the elderly people in Okinawa, etc. Modern research have verified extremely low prevalence of chronic disease in these populations. All these people had a cumulative exposure to very low levels of serum cholesterol. So, instead of looking at one population at a time, we should look for broader patterns.

        A good article to browse is “The epidemiology of coronary heart
        disease in South Africa”, which you can find from google.

        CARDIOVASCULAR JOURNAL OF SOUTHERN AFRICA (SAMJ Supplement 1 February 1999)

  16. jluchte says:

    Nutritional composition is discussed and is varied around the world (now and historically). Exercise is also variable.

    I wonder about the influence of stress…

  17. WilliamLawrenceUtridge says:

    The paleo diet is such a nonstarter. It’s proponents are enthusiastic, like proponents of so many fads, but it’s just so irrational. There are too many confounds, it doesn’t make sense in the first place (which paleo diet? Do we count tomatoes?) and the arguments shift goalposts and declare non-Scotsmen so frequently it’s like watching a game of Calvinball played in Uganda (Last King of Scotland reference BTW). The certainty is so outrageously out of step with the evidence. Yes, unprocessed and minimally processed foods are good for you. Yes, exercise is good for you. That’s not “paleo”, that’s what the USDA, CDC, doctor and yo’ mama recommends.

    1. Are you familiar with the recommendations of the USDA?

      1. WilliamLawrenceUtridge says:

        Passingly, they change year to year but they always emphasize whole foods, fruits, vegetables and whole grains over meats and fats.

  18. windriven says:

    I’d like to understand: what is the point of consuming a “paleo diet”? Consuming a “paleo” diet asks me to eschew bread, beans, beer, booze, beets, blini, and buttered pecan ice cream. Why? What is the payoff? What is the advantage over a balanced diet that includes all of the cornucopia of wonderful things that people stuff in their pie holes?

    I’ve spent a little time checking out some of the “Paleo” sites and all are long on promise and short on documentation. How is this not just another magic diet fraud? What is it about some people that compels them to embrace exclusionary diets as some sort of miracle?

    1. Garett says:

      First, there’s nothing about paleo that excludes beets – I eat plenty of beets. Second, any paleo aficionado dogmatically advocating a strict list of foods you can eat misunderstands the concept. The point is to find the combination of nutrient dense foods that work for you using the elimination/challenge protocol. That is, for 30 days or so you eat a strict paleo diet and let your gut heal up (i.e., regenerate new, undamaged, enterocytes). Then, you try introducing foods one by one to see if they cause problems or not. Some people can handle dairy, others cannot. Some people can handle grains, others can’t. Some people can magically handle everything and so they keep eating that way – great for them (I’m jealous).

      I eat this way because I don’t enjoy feeling like crap all of time and through this protocol I’ve been able to identify a set of foods that consistently make me feel terrible and wreck my digestion. So I avoid them. I don’t understand what’s so controversial about that idea. Why is it such a huge problem that people want to avoid foods that make them feel terrible? I still eat some of the foods you mention because they don’t bother me – others I strictly avoid.

      Since I’ve starting eating like this, my digestion has normalized. I’ve had digestive problems my whole life and now I’m twice daily regular (TMI, sorry) since I can’t remember when. I don’t drink beer because my joints feel on fire (I have a history of RA in my family), but I can tolerate a little red wine. I can do some types of cheese but I can’t do ice-cream or butter/casein. Beans are no problem. I can’t handle whole grains (the outer portions are the hardest to digest and those are in-tact in whole grains) but processed white flour is fine (I love a good dumpling every now and then).

      So the point isn’t to abide by a dogmatic list of foods – it’s to experiment through elimination/challenge and find the ones that work for you. I simply don’t understand people’s visceral reactions paleo when it’s simply trying to avoid things that make them feel terrible. It’s true that paleo tries to identify foods that, on average, are more likely to people feel terrible (e.g., grains, dairy) but that won’t be the case for everyone.

      The point of the strict paleo phase may seem restrictive but it has a purpose. The point is to let things normalize a bit so you have a better reference point for what makes you feel terrible. This is purely anecdotal, but the people I know who have tried this method starting out saying how grains never bothered them, so why should the eliminate them? After cutting them out for a while and then reintroducing them, they experienced a bad digestive reaction immediately. Cutting things out for a while gives a better reference point for whether it causes problems or not since your body may actually adapt to feeling like crap and you just won’t notice it until you have a “better” reference point.

      Finally, I wanted to touch on this briefly:

      “I’ve spent a little time checking out some of the “Paleo” sites and all are long on promise and short on documentation”

      I will point out that there are a number of good books on Paleo that provide a lot of documentation and give references to the literature they draw from. I suggest checking one out. I mean, what do you have to lose? That’s my other critique of people who bash on paleo – I doubt they seriously understand it (i.e., nurtient dense, elimination/challenge). I think that if you are going to critique something you should be sure you truly understand it (I’ve been guilty of not doing that plenty of times). If you read the books and still don’t find it compelling, so be it. All you’ve lost is a little time reading and $20. I’m always weary of someone who critiques something but is unwilling to learn more about it. I like these two:

      http://www.amazon.com/The-Primal-Blueprint-Reprogram-effortless/dp/0982207786/ref=sr_1_1?ie=UTF8&qid=1378990912&sr=8-1&keywords=primal+blueprint=

      http://www.amazon.com/The-Paleo-Solution-Original-Human/dp/0982565844/ref=sr_1_1?ie=UTF8&qid=1378990999&sr=8-1&keywords=paleo+solution

      1. windriven says:

        “Some people can magically handle everything and so they keep eating that way – great for them (I’m jealous).”

        I guess I’m one of those lucky ones. Most, but not all, of those I know also seem to be in that number.

        But Garett, the GI issues you mention and the protocol you used to eliminate foods that exacerbate those problems are not, from my reading of the pro-paleo activists, the point of the paleo diet. Guys like Mercola advocate the paleo diet as a general panacea and there is just no science to support that.

        I’m glad you got a handle on your issues. But the elimination/challenge process that you used isn’t specific to the paleo diet.

        1. Garett says:

          Hi winddrive, thanks for the response!

          “I guess I’m one of those lucky ones. Most, but not all, of those I know also seem to be in that number.”

          That’s great. I will just add, however, that at least two people I know although thought the were the “lucky ones” until I convinced them to give it a shot. I told them they have nothing to lose. If it doesn’t work – you still ate healthy for 30 days and now you can go back to eating whatever you want. But, when they tried to go back, they realized that weren’t so much “lucky” as they had just become accustomed to feeling like crap – that’s the relative piece I was talking about. Now, to be honest, these two people were my parents so there could certainly be a genetic factor there.

          “But Garett, the GI issues you mention and the protocol you used to eliminate foods that exacerbate those problems are not, from my reading of the pro-paleo activists, the point of the paleo diet. Guys like Mercola advocate the paleo diet as a general panacea and there is just no science to support that”

          I’m actually not aware of Mercola so it sounds like there are some Paleo sub-factions emerging! I’m more familiar with Robb Wolf who came to Paleo via the GI/celiac route so he does focus very much on the digestive portion (and the overall health benefits). There are a few other “specialty” areas as well, where use paleo to address autoimmune disease flare ups (there is a huge literature on food and autoimmunity). I do agree 100% though that there’s nothing about this that’s specific to paleo. Indeed, the elimination/challenge protocol is used to great success in practice to find food intolerances/sensitivities. As I said, before, however, the strength of paleo is that it starts by eliminating some foods that are more likely to be offenders (e.g., grains, dairy). Maybe this is why people are talking more about paleo as a template rather than a diet? You start with a guide and then tweak as needed.

          I do have to touch on the last part of that sentence though. I get a little peeved when I see people using “science” like it’s some hammer to be used to beat the ignorance out of the populus. The problem here, is that most if not all of these dietary approaches are still theories. What does that mean? It means that different people are drawing from evidential bases and integrating/synthesizing that information to come up with an explanation for an observation.

          However, it often stops there and is never taken to the next step of *testing* the theory. So I do feel that saying there’s no science to support it is a bit disingenuous. It’s not that there aren’t evidential bases that support the theory, it’s that the theory hasn’t been aadequately tested. However, both of those steps are invaluable parts of the scientific method. If paleo proponents were saying “eat this because a magical being told us so,” then yes I would agree with you 100% but that’s clearly not what’s going on. As with anything that’s actually scientifically supported, time will tell. The theories will be tested, the data will accumulate, and eventually the scientific community will develop a shared consensus of what’s true. That might not be paleo and that may never happen in our lifetimes, but at this point I do think saying paleo is unscientific is a step too far. Perhaps it’s better to say, time has been insufficent to allow the scientific method to tell us if paleo is useful?

          1. windriven says:

            Garett,
            We have to be careful not to set up straw men for each other.

            You are, as I understand it, using paleo diet to describe an elimination/challenge process that is tied to paleo only so far as paleo established your elimination starting point. Elimination/challenge protocols are often used to identify food intolerances. Frank allergies can generally be identified through laboratory tests. You might read Scott Gravura’s column in today’s SBM.

            The Paleo diet as it has been discussed in this blog refers to the general advocacy of a diet thought by some to mimic the diet of our paleolithic ancestors and advanced as ‘good’ largely because it is ‘ancient’.

            In using the elimination/challenge protocol you are conducting a series of experiments that, presuming your are carefully tracking challenges and results, could be characterized in a very limited way as scientific.

            But your experiment is not blinded, the responses are subjective and the number of subjects is one. So this cannot be generalized. In effect you have conducted an experiment, applied the result to your own lifestyle and judged it successful.

            Here we part company:

            “but at this point I do think saying paleo is unscientific is a step too far.”

            There is no scientific evidence that I am aware of that links a “Paleo Diet” to any particular benefit in a general population. That doesn’t mean that science will never establish such a benefit but until it does it there is no scientific basis.

            ‘No scientific evidence’ does not mean the same as ‘untrue.’ It means unproven. It means that proponents of the hypothesis need to do the work of proving it by establishing scientific evidence supporting it. Asking others to give credence to it before that work has been done is mightily presumptuous.

            Look, would you prefer to fly in an airplane that was designed with wings copied from archeopteryx fossils or an airplane designed using scientific principles? We use scientific principles rather than gut feelings because we have tested them and established their limits.

            And when science hasn’t established something either way we fall back to prior plausibility; sort of a directional arrow based on the many scientific principles that have been established.

        2. Garett says:

          Speaking of straw men, your post below misrepresents nearly every one of my points.

          =================================
          “Elimination/challenge protocols are often used to identify food intolerances. Frank allergies can generally be identified through laboratory tests. You might read Scott Gravura’s column in today’s SBM.”
          =================================

          I know well the difference between a food allergy and intolerance, and if you read my post I said elimination/challenge is used for intolerance and sensitivities. I know I’m not allergic to lactose, but I also know I’m sensitive to it because my digestion blows up when I ingest it. I read that article this morning – it was great. Nothing about what I’ve said contradicts that. I mentioned nothing about food allergies.

          =================================
          “The Paleo diet as it has been discussed in this blog refers to the general advocacy of a diet thought by some to mimic the diet of our paleolithic ancestors and advanced as ‘good’ largely because it is ‘ancient’.”
          =================================

          Just because that’s how it’s discussed in this blog is not what people who practice paleo actually believe. As I said before, if you take the time to learn about you’ll realize that virtually no one in the paleo community actually advocates that we are mimicking the diet of our ancestors. We acknowledge that if that was the case, we’d be eating none of the things we do now because none of them existed. Nobody says the diet is good because it’s ancient. If you want to speak of straw men. Maybe the people on this blog would do well to step outside of their insular community and learn about a topic before lambasting it.

          =================================
          “But your experiment is not blinded, the responses are subjective and the number of subjects is one. So this cannot be generalized. In effect you have conducted an experiment, applied the result to your own lifestyle and judged it successful.”
          =================================

          Not once did I say that I was practicing science through my elimination challenge nor was I saying that this is why it’s scientific. Generalization is meaningless if you are only trying to explain a very specific example. I’m not trying to say my results generalize. If you read my actual post, you’ll see that I was talking about finding a unique combination of foods *that worked for me.* I was only interested in what works for me – why should I care if it generalizes? I acknowledge that plenty of people can handle the foods I can’t. Yes, I have judged it successful for my life because my life is the population – I don’t need to sample from a population and then use inferential statistics to generalize inferences – I have the entire population!

          =================================
          “There is no scientific evidence that I am aware of that links a “Paleo Diet” to any particular benefit in a general population. That doesn’t mean that science will never establish such a benefit but until it does it there is no scientific basis”
          =================================

          Simply because you are not aware does not make the evidence nonexistent. Listen, “scientific evidence” is not something than be applied in a vacuum. Science is not some all knowing being. Science is used to instill confidence in inferences drawn from data. When you say “scientific evidence,” evidence for what? How about evidence showing that grains wreak digestive havoc? That seems like a benefit to the general population. You are getting so caught up on the “eat like our ancestors” argument, which is a complete and utter straw man.

          =================================
          “Look, would you prefer to fly in an airplane that was designed with wings copied from archeopteryx fossils or an airplane designed using scientific principles? We use scientific principles rather than gut feelings because we have tested them and established their limits.”
          =================================

          This is a very poor analogy. Do you know why we know airplanes work? Because we can use them. We can apply our designs and our scientific knowledge and we can see that planes clearly work. In the same manner, we could see that “wings copied from archeopteryx fossils” would clearly be inferior. I draw from established research showing that very specific types of foods can digestive distress and other problems (these foods also happen to be eliminated on paleo), I apply that knowledge to see if I feel better and I take meticulous notes (I’ve kept detailed journals for over a year), I observe the results, and voila I feel better. I now know that eliminating that food works and I have a very specific reason for why.

          What’s my other option? Say, oh. Well, no scientific study has tested these specific foods on people my age from my same background who have the same activity level as me (etc) to see if there’s reason to believe they will be problematic. I guess I should keep eating them and feel terrible. That’s ridiculous.

          Nobody is using paleo because of gut feelings. Look at Robb Wolf or Mark Sisson – they spend hours and hours analyzing research. I and they are making informed decisions based on research and paying attention to the results of applying that information and correcting as necessary.

          It just blows my mind that in a “science-based” forum the first reaction is to deride anything unconventional rather than spending some time learning about it. How scientific is it to immediately dismiss an observation because it does not conform to your beliefs? I’m on the tail end of PhD so I understand the value of science, reason, and research, but too often it seems that we are starting with the hammer (i.e., science) and looking for nails to pound instead of the other way around.

          1. windriven says:

            Garett, there was not a single straw man in what I wrote. You proclaiming one does not make it so.

            “How scientific is it to immediately dismiss an observation because it does not conform to your beliefs? I’m on the tail end of PhD so I understand the value of science, reason, and research, but too often it seems that we are starting with the hammer (i.e., science) and looking for nails to pound instead of the other way around. ”

            It is clear from these two sentences that your doctorate is not in one of the sciences. Further, no one “dismissed an observation”. I didn’t. Novella didn’t. To the best of my recollection none of the commenters did. An observation is not an experiment nor a hypothesis. It is just an observation.

            Science Garett, is not a hammer and it certainly doesn’t look for nails to pound.

            You said, “How about evidence showing that grains wreak digestive havoc? ” Do you understand that this is a statement utterly lacking scientific validity? You have made a wildly broad and emotional pronouncement.

            It is scientifically accurate to say: A small portion of the US population experiences an autoimmune reaction to a protein in some grains called gliadin. That is not the only scientifically accurate statement that can be made about grains as a constituent of the human diet, but it is one example. “Grains are bad for people” isn’t.

            Your personal anecdote does not constitute a prescription for changing the dietary practices of the species.

            I’m happy to discuss this with you for as long as you’d like. Or not. Your choice. But from here on out you’re going to have to be very specific and frame your assertions carefully. If your definition of Paleo Diet differs from others then you need to lay it out your definition clearly. And if you have an actual hypothesis that you are trying to forward lay it out succinctly.

          2. windriven says:

            “Simply because you are not aware does not make the evidence nonexistent. ”

            I absolutely agree. Lay out citations from the peer reviewed literature supporting your point. But please, let’s have some context. What exactly is your point???

        3. Garett says:

          I’m not making emotionally driven statements, I”m drawing from the literature. May you should spend a little bit of time on pubmed before you decide to be condescending:

          http://www.ncbi.nlm.nih.gov/pubmed/?term=Spectrum+of+gluten-related+disorders%3A+consensus+on+new+nomenclature+and+classification

          Gluten sensitivity is a spectrum with celiac being the extreme. Thus, my statement was not an over exaggeration or emotionally driven. It reflects the current SCIENTIFIC thinking.

          1. windriven says:

            “I’m not making emotionally driven statements”

            Garett, don’t change the discussion and then claim I’ve misrepresented your statements.

            You said, “How about evidence showing that grains wreak digestive havoc? ”

            That is a wildly broad and emotional statement. It is not borne out anywhere in the paper that you referenced. I’ve tried to explain to you some of the scientifically valid statements that you could make and that, incidentally, the article that you referenced would support. Is the problem that those scientifically defensible statements don’t lead to the conclusion that you want?

            .

          2. That’s a weird interpretation of the paper you cited. Celiac is the “extreme” really? Wheat Allergy is somehow not an extreme? Even though you could have anaphylaxis in less than an hour?

            The particular paper you are quoting talks about classifying someone as Gluten Sensitive but only after a double-blind challenge. It makes no mention as to how many people actually have passed this nor any mechanism. It references a small n=34 double-blind trial of IBD patients. However having eaten a lot of gluten free products and even baked some I would question the ability to blind people who are already convinced they have a problem with gluten.

      2. WilliamLawrenceUtridge says:

        The point is to find the combination of nutrient dense foods that work for you using the elimination/challenge protocol. That is, for 30 days or so you eat a strict paleo diet and let your gut heal up

        Why on earth call it “paleo” then?

        I don’t understand what’s so controversial about that idea.

        It’s not the idea you describe (which is basically “eating pretty much within the USDA guidelines”). It’s the stupid, stupid name, and the fallacious implication that how humans must eat for good health somehow dates back to the paleolithic era. The fact that people describe it in terms of eating like a caveman, or the “original” diet, and any other reference to there being some sort of nutritional Eden.

        I simply don’t understand people’s visceral reactions paleo when it’s simply trying to avoid things that make them feel terrible.

        Because that is the very first time I have ever heard it described in those terms. I’ve heard lots of arguments for “primitive” foods, for eating “the original” foods like bananas (but not the original banana which is borderline inedible) and claims that wheat or a whole category like “grains” are somehow bad, while other foods like apples and tomatoes and raw meat) are somehow more natural, or better, or some other nonsense, because of evolution.

        Perhaps you are right, and we’ve misunderstood the paleo diet to date. Based on your comments, we have apparently totally misunderstood the paleo diet to date.

  19. Richard Mjödstånka says:

    I’d like to add that I agree with the general conclusion by Harriet Hall. The Kitavans do not teach us anything what we didn’t already know.

    Even today, the the wheat intake of rural Tunisians is 3 times greater compared to their urban cousins. The CHD mortality is significantly lower among rural Tunisians compared to city dwellers who show 2-fold greater intake of red meat. I find some of arguments and speculations presented here rather ridiculous.

    What can paleo-framework teach us when it comes to Near-East? The paleo framework based on the, appeal-to-nature fallacy is what it is, a fallacy which cannot stand even the mildest form of scientific scrutiny.

    Analyzing Recent Coronary Heart Disease Mortality Trends in Tunisia between 1997 and 2009
    http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0063202

    1. Garett says:

      I think the research on the digestive distressing qualities of grains might say otherwise: http://www.ncbi.nlm.nih.gov/pubmed/23983652

      Bottom line is that many people do experience sensitivites to grains even if they are not truly allergic reactions (e.g., celiac). You can debate the merits of “we haven’t evolved to eat grains” all you want, but grains wreak havoc on digestion. Sans proper digestion, all sorts of bad things happen.

      1. windriven says:

        Garett,
        What do you think that the article that you referenced means?

        1. Garett says:

          It means that people can react poorly to food substances for any number of reasons, even if they are not allergic (e.g., wheat allergy) or autoimmune (e.g. celiac). They acknowledge that gluten may be one of these substances. That is, people can still be sensitive to gluten even if it’s not an allergy or autoimmune reaction. Indeed, current thinking is that gluten sensitivity is a continuum or a spectrum. However, they also state that gluten is one emerging hypothesis for why people might be sensitive to wheat, but it’s highly probably that other gliadins are implicated. So, in short, people can have food sensitivities that are neither allergic nor autoimmune in nature. What do you think it means?

          1. windriven says:

            Did you actually read the article? This from the author’s conclusion:

            “Despite the frequent rush to treat a wide range of gastrointestinal and nongastrointestinal symptoms with a gluten-free diet, healthcare providers should keep several important practical issues in mind. Due to the relatively low prevalence of celiac disease, it is always advisable to formally test for this condition before instituting a gluten-free diet. ”

            He argues that clinicians should be aware that some patients experience gastrointestinal disturbances following wheat ingestion that are not allergies. OK. Nothing controversial there.

            What is it in this piece that you find to be such an “AHA” moment?

        2. Garett says:

          My points are very simple and I’ve made them before, but I’ll reiterate and then I am afraid I’m done with this exchange. There is plenty of scientific evidence to show that people may experience digestive distress when ingesting grains (there’s an entire literature on grains and IBS), and this may occur even in the absence of an allergic or autoimmune reaction. If this happens, avoid grains. The end. Why eat something that makes you feel terrible. Guess what? What I just described is precisely what the paleo community advocates. I understand that you may not like paleo and that’s fine. But I think your expectations what constitutes scientific support for paleo are drastically misplaced. It reminds me of theists saying that they won’t accept evidence of evolution unless you show them one animal changing into the other.

          1. windriven says:

            “There is plenty of scientific evidence to show that people may experience digestive distress when ingesting grains ”

            “The end.”

            Then why all the highly charged rhetoric, Garett? Nobody would disagree that there is abundant evidence that SOME people may experience digestive stress after ingesting grains. If that was the message that what you call the “paleo community” was advocating, no one would disagree, Dr. Novella would never have written this post and none of us would have anything negative to say.

            ” I understand that you may not like paleo”

            Whether or not I or anyone else “likes” paleo is immaterial. You are welcome to follow any diet that appeals to you. But some advocates promote the paleo diet as a superior diet for the general population. Which brings us back to Dr. Novella’s post and far away from the very narrow definition that you are now embracing.

  20. Instead of constructing straw men and beating on them, it might be more productive to see how the paleo community defines the diet and addresses these issues:

    “We call it “paleo” for the same reason that we call it “Latin”, even though we have absolutely no idea how it was spoken. Just as Latin scholars attempt to maintain something syntactically analogous to written Latin, paleo dieters attempt to maintain something nutritionally analogous to an ancestral human diet.

    This is where we have to start using science to draw tentative conclusions from the evidence we have. And while it’s tempting to get into speculative arguments about human prehistory, at the end of the day, we have to ask ourselves: What is the biochemistry of humans? How does human metabolism work, today, right now?” -What Is The Paleo Diet, Anyway?

    JS

  21. Garuno says:

    The known carcinogen sodium nitrate is found in a wide variety of vegetables, and in high quantity (i.e. more than in bacon) in vegetables such as curly kale and celery.

    Perhaps you can demonstrate how the known carcinogen sodium nitrate is okay in celery (which is often used as a basis for producing “no nitrates added” bacon) but totally not okay in bacon. After all, sodium nitrate is a known carcinogen.

    So can you?

    1. Mie says:

      Perhaps the context matters as well? How much e.g. celery do you consume in one sitting? And what about other nutrients found in celery vs. bacon?

    2. daedalus2u says:

      I would like a citation for the claim that sodium nitrate is a “known carcinogen”. I am pretty sure that it is not, that it is actually an anti-carcinogen.

      There is theoretical speculation that nitrates in the diet can foster production of nitrosoamines (which are carcinogens) in the gut, but there isn’t any good in vivo data that suggests that dietary nitrates are carcinogens. There are very likely other compounds in gastric contents (such as ascorbate) which prevent formation of nitrosoamines.

      Nitrate is a normal product of metabolism. Humans synthesize nitrate. Humans also synthesize nitrite. Rats and mice have been given nitrite (up to 5,000 ppm in drinking water) for a couple of years and there was no apparent excess cancer.

      Nitrate is very likely an important nutrient, and is very likely a significant component responsible for the benefits of a diet rich in green leafy vegetables (green leafy vegetables have a few thousand ppm nitrate).

  22. Garuno says:

    I should have preceded my first comment with “@stanmrak”, as it didn’t appear anywhere near his. No matter.

    To answer your suggestion about context, I think the problem here is that Stanmrak was emphasizing that sodium nitrate is a known carcinogen, which in my view is a specific attempt to _remove_ context, and that is what prompted my own comment.

    His point sounds explicitly designed to be non-negotiable to me, so I took the liberty of reminding him of other sources of the known carcinogen sodium nitrate in our food. There are many.

    I agree with you that the amount of celery consumed is important in determining how much of the known carcinogen sodium nitrate you are consuming, but that point is rather obvious, and applies equally to bacon. And it leaves us back where we started, that if sodium nitrate* is a known carcinogen, it is one that is found both in processed meats and in fresh, unadulterated vegetables.

    (*Actually, in the example I introduced to the discussion, bacon, sodium nitrite is used, and in long-cured meats like salami, it would be sodium nitrate. I doubt that stanmrak is ready at this point to consider them as anything other than identical – and very bad, just so long as they’re in processed food.)

    1. WilliamLawrenceUtridge says:

      The problem with comment threading seems to be browser-related. If possible, try switching to Chrome, that seems to be the most reliable.

  23. The Kitavan “paradox” is consistent with the line of research in the papers cited here and in the comments below http://hopefulgeranium.blogspot.co.nz/2013/09/the-elegant-solution.html
    the kitavan diet is low in two obesigenic foods – linoleic acid (omega 6 PUFA), and sugar or refined starch.
    If you substitute tinned fish (packed in soy oil) for the fresh fish you will probably see the same obesity epidemic as in Vanuatu. substitute two-minute noodles for the taro as well, and it becomes certain, but the oil is probably the one thing that makes any high-carb diet unsafe, at least in terms of obesity.

    1. WilliamLawrenceUtridge says:

      The definition of “obesogenic food” is any macronutrient consumed in excess of expenditure. Protein gets converted to fat, sugar gets converted to fat, and fat gets stored. Substitute taro that doesn’t require farming and is available in unlimited quantities, they will get fat. Substitute fresh fish that doesn’t require farming and is available in unlimited quantities, they will get fat.

      It’s the calories.

      1. Wrong – there are foods that make you store fat. When you are storing fat, you stay hungry, because you cannot access the energy you are storing. You need more calories to live/work and store fat at the same time. This is what the papers prove – there is no reason for one caged mouse to eat more than another, convenience and access stays the same, what changes is the fat storage. Read all the papers linked in that blog post and comments.
        If it was just food that doesn’t require farming, then everyone would be fat, and rich people would get fat more often than poor people, but this is the opposite of what happens, because rich people have access to better quality food.

        1. For example,
          “In the high protein group, 467.8 kcal were needed to produce a weight gain of 1 g, whereas the high carbohydrate group only needed 67.8 kcal to produce the same weight gain, which almost exclusively represented an increase in adipose tissues.”
          It is that increase in adipose tissues that is the key. the response to some foods increases the numbers of fat cells (in this experiment, it was corn oil plus high sugar). The response to the same calories from different foods (in this case corn oil plus high-protein) leaves the fat cells as they were or reduces them.
          Without this response of the fat cells you cannot get fat. Not all food combinations can produce it. What is possible in mice is certainly not impossible in humans, and explains closely what we see in the human world around us – what are human foods that meet these fattening critera?
          Donuts are made from refined starch, sugar and omega 6 oil. Potatoes are mainly starch. What will make you fatter – half your diet as donuts (1,000 KCal daily) or half your diet as potatoes (1,000 KCal daily)?

          1. WilliamLawrenceUtridge says:

            And this is where you might run into trouble. Perhaps in mice, fat cells increase in numbers. In humans, once you reach a certain age, fat cells increase only in size.

            Which is easier to eat, 1,000 calories of donuts or 1,000 calories of potatoes?

        2. WilliamLawrenceUtridge says:

          No, you eat more because you are hungry. The problem is not that certain foods magically cause more fat to be stored, the problem is certain foods have less of a satiety effect, which makes you eat more.

          People aren’t mice.

          Among the wealthy, males are obese and women are thin. Among the poor, the pattern is reversed. Food volume and exercise.

  24. Sorry, I have left too many variables in that last thought experiment.
    Instead of answering it, I suggest you read this paper, then read the citations therein: https://www.landesbioscience.com/article/20689/full_text/#load/info/all
    It is a truism to say that extra calories are needed for weight gain. A scientist will look for answers as to why these extra calories are being consumed, and why, being consumed, they sometimes lead to weight gain rather than more activity or less appetite.
    If the answers they get from animal experiments are consistent with the patterns seen in human epidemiology and clinical case studies, this will suggest possible improvements in human diet.
    The improvements suggested by these papers – limiting dietary omega 6 below current western intakes, obtaining dietary EPA and DHA, limiting sugar below current western intakes, reducing insulin/glucagon ratio by limiting carbs and consuming adequate protein, are all consistent with the various Paleo templates and provide one rationale for explaining how they work, though other explanations may simultaneously be available from other kinds of diet research, for example, research into gliadin and wheat intolerance

  25. Sm227 says:

    Thank you for not just this article, but for this entire site. I’m a college senior with hopes to attend med school in the fall, but I hear so many unreasonable things from young women who have latched on to science-y sounding things to… Honestly, to justify food issues. It’s so difficult to have somewhere to tell them to look for things like why protein denaturing isn’t as scary as it might sound or why extreme diets posing as science are not usually balanced ways to live. It’s so unfortunate that for this one site there are a million pseudoscientific sites with much louder presences. But this is a great resource and I will def. be sending people here!

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