"Man the Fat Hunter" Paper Defines Paleo Diet As Meat-Based, Plant-Poor

I continue to read comments on my blog, and around the web, suggesting that anyone who believes that paleo diet is meat-based and low in carbohydrates is at least misinformed and at worst stupid.  Supposedly, by the time I had written Farewell To Paleo [which I have updated with references supporting my supposedly subjective evaluation of meat-based diets], some panel of experts had already decided that paleo diet is not necessarily meat-based, nor high in fat, nor low in carbohydrates, and I was well behind the learning curve.  Paleo 3.0 had arrived without my knowing it.

Or so some would like to think.

Perhaps unbeknownst to some people, "paleo diet" is short for "paleolithic diet,"  referring to the diet that humans evolved to eat during the so-called stone age.   The people who originally promoted paleolithic diet as a modern method for supporting health and preventing disease conceived of a modern paleo diet as an attempt to replicate the salient nutritional features of the diet that supported human evolution using foods from the food groups believed to constitute prehistoric paleolithic diets.

Anthropologists, biochemists, and biologists who study the evolution of humans and human nutrition and the recent diets of hunter-gatherers have produced the evidence for the model of paleolithic diet that informs Loren Cordain's works.  Among these people it seems there is a general agreement that prehistoric human diets were meat-based, high in animal protein and fat, and low in plants and carbohydrates.  There are dissenters who have attempted to argue against this notion, such as Richard Wrangham and Katherine Milton, and, in the medical community, perhaps David Jenkins, but these individuals are in the minority.  The majority adheres to some form of the Man The Hunter hypothesis, i.e. that increased carnivory separated the human line from our closest primate relatives; that increased meat-eating coupled with decreased plant-eating drove human evolution.

On February 21, 2012, after several people commenting on this blog had repeatedly tried to convince me that paleo diet is not necessarily meat-based, high in fat, or low in carbohydrates, Paul Jaminet posted the following message on the Facebook page for the Journal of Evolution and Health:

In case you have trouble reading it, it says:

"I'd like to welcome Miki Ben Dor to the journal effort. Miki was the lead author on the excellent recent paper "Man the Fat Hunter" http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3235142/" [Jaminet forgot to hyphenate Ben-Dor's name.]

Does this paper depart from the hypothesis that prehistoric paleo diet was meat-based and assert that humans evolved on random combinations of meat, vegetables, fruits and nuts, so that any combination thereof constitutes a paleo diet?

No.  Here is part of the abstract:

"We show that rather than a matter of preference, H. erectus in the Levant was dependent on both elephants and fat for his survival. The disappearance of elephants from the Levant some 400 kyr ago coincides with the appearance of a new and innovative local cultural complex – the Levantine Acheulo-Yabrudian and, as is evident from teeth recently found in the Acheulo-Yabrudian 400-200 kyr site of Qesem Cave, the replacement of H. erectus by a new hominin. We employ a bio-energetic model to present a hypothesis that the disappearance of the elephants, which created a need to hunt an increased number of smaller and faster animals while maintaining an adequate fat content in the diet, was the evolutionary drive behind the emergence of the lighter, more agile, and cognitively capable hominins."

They believe that H. erectus in the Levant was so dependent on dietary fat (and meat, particularly of elephants) for survival,  that the disappearance of the elephants drove them to hunt smaller animals, and this need to hunt smaller, faster, more agile animals coupled with a presumed physiological need for dietary animal fat provided a selective pressure that favored survival of a lighter, more agile, and smarter hominin, namely H. sapiens.

They expressly argue against the idea that human evolutionary diets could have been plant-based.  For example, they state that human ancestors needed to consume animal fat because they couldn't eat enough plants to meet nutrient requirements:

"The need to consume animal fat is the result of the physiological ceiling on the consumption of protein and plant foods."

Under the heading "The Obligatory Animal Fat Dietary Model" they use the standard argument for an animal fat-based based paleolithic diet using the expensive tissue hypothesis; they think our supposedly small gut coupled with our large brain provide evidence that meat-eating fueled human brain evolution:

"The more compact, the human gut is less efficient at extracting sufficient energy and nutrition from fibrous foods and considerably more dependent on higher-density, higher bio-available foods that require less energy for their digestion per unit of energy/nutrition released. It would therefore appear that it was the human carnivorousness rather than herbivorous nature that most probably energized the process of encephalization throughout most of human history."  [Emphasis added]

(Ben-Dor et al incorrectly state that encephalization took place during human history, when presumably it actually took place in prehistory, i.e. before written records.)

Under the heading "The physiological ceiling on plant food intake" they argue that plant foods could not have been a significant part of prehistoric diets for all the time-worn reasons given by previous paleo diet theorists:  takes too much time to gather plants, impossible to get adequate calories from raw plants, too many toxins and antinutrients in plants, no control of fire by H. erectus, lack of large cecum in human gut.  


You will find this passage in their paper:

"Similarly, modern hunter-gatherer (HG) groups, despite having access to fire and metal tools, also seem to have a strong preference for carnivorous foods over vegetal foods ([53]:682), a notion also supported by a recent study [75] that emphasizes limited consumption of carbohydrates by present day HG groups.

"Indeed, an analysis of nine HG groups for which detailed dietary information exists ([76]:166) shows that five groups, located in an area abundant in vegetation, consumed only a meager amount of plant foods (17% of calories on average)."[Emphasis added]

This paper also includes a line I think I might have read first in Paul Jaminet's book, The Perfect Health Diet:  "In fact, the natural diet of mammals is a high-fat diet." (Apparently they imagine that no mammal could break this supposed general rule, not even it it was peculiarly dependent on glucose to fuel its extraordinary brain.)

So, there you have it:  These archaeologists and anthropologists, like others before them, believe that humans probably evolved on (and presumably are presently adapted to) a diet consisting largely of meat and fat with "only a meager amount of plant foods" and "limited consumption of carbohydrates."  They apparently believe that because we are mammals, our natural diet is a high-fat diet.

Apparently Ben-Dor et al have not gotten the update on paleo diet from the blogosphere.  Anyone want to send them version 3.1?

Of course those internet experts know more about paleolithic diet than these anthropologists and archaeologists, right?

Just like Denise Minger, who admits having no formal training in statistics or medicine, knows more about statistics than Richard Peto, PhD, the Professor of Medical Statistics and Epidemiology from Oxford University who was elected a Fellow of the Royal Society of London (for the introduction of meta-analyses) in 1989, and was knighted (for services to epidemiology and to cancer prevention) in 1999, and worked on the Cornell-Oxford-China Project, right?

The same way that Anthony Colpo, who has no medical training and has never published any peer-reviewed cardiovascular disease research,  knows more about atherosclerosis than WC Roberts, who has authored several books on cardiovascular disease, has spoken at more than 1,300 medical meetings, serves as editor-in-chief of The American Journal of Cardiology, and with colleagues published more than 1,150 peer-reviewed articles on cardiovascular disease in medical journals, right?

And Gary Taubes, a science writer with no experience in bench obesity or medical research, and no peer-reviewed publications in the field of obesity research, knows more about nutrition and obesity, than, say, George Bray, Ph.D., Boyd Professor and Chief of the Division of Clinical Obesity and Metabolism at Pennington Biomedical Research Center, who over his 40 year career has authored or coauthored more than 1,700 publications, ranging from peer-reviewed articles to reviews, books, book chapters and abstracts, primarily in the field of obesity research.

If you think I am falling for a fallacious argument from authority, you don't understand that fallacy.   As explained at FallacyFiles.org, an argument relying on authority is fallacious only if in the question under consideration, 1) no expertise is necessary or possible, 2) the cited authority is not a recognized expert in the field, 3) the authority is expert, but not disinterested, or 4) the authority is an expert, but his opinion varies markedly from the consensus of experts in his field.  Fallacy Files recommends this procedure for determining whether an argument from authority is fallacious or not:

To sum up these points in a positive manner, before relying upon expert opinion, go through the following checklist:

• Is this a matter which I can decide without appeal to expert opinion? If the answer is "yes", then do so. If "no", go to the next question:
• Is this a matter upon which expert opinion is available? If not, then your opinion will be as good as anyone else's. If so, proceed to the next question:
• Is the authority an expert on the matter? If not, then why listen? If so, go on:
• Is the authority biased towards one side? If so, the authority may be untrustworthy. At the very least, before accepting the authority's word seek a second, unbiased opinion. That is, go to the last question:
• Is the authority's opinion representative of expert opinion? If not, then find out what the expert consensus is and rely on that. If so, then you may rationally rely upon the authority's opinion.

If an argument to authority cannot pass these five tests, then it commits the fallacy of appeal to misleading authority.

If you apply these five tests to Denise Minger's authority on the Cornell-Oxford-China Project, or Anthony Colpo's authority on diet and cardiovascular disease, or Gary Taube's authority on diet and obesity (or diet-related diseases), you will see who commits the fallacious appeal to authority. 

Of course, the consensus could be wrong.  But, when 50 or more years of research has produced enough evidence in support of a particular hypothesis to produce a wide consensus in a field, such as the lipid hypothesis, then you need really extraordinary evidence to overturn that hypothesis.

I highly doubt that Ben-Dor et al are going to change their view of paleolithic diet because some bloggers have decided that "paleo" includes plant-based diets with only meager amounts of meat and fat.

Just to be clear, I am not in this post agreeing, nor disagreeing, with any of the hypotheses of the Ben-Dor et al paper, so far as they apply to defining paleolithic diet or explaining the emergence of H. sapiens from H. erectus.   Even if their hypothesis about how modern humans emerged is strongly supported by evidence I do not believe that it in any way establishes or strongly supports the idea that a meat-based, high-fat diet with a meager amount of plant foods and limited amount of carbohydrates best supports human health in a modern context.  The direct way to discover the effects of foods on health of modern people in modern nations is to study the effects of various foods on modern people in modern nations, not speculate about how H. sapiens emerged.

In fact, if you believe that Ben-Dor et al have shown that a fat-based carnivorous diet is the best to support human health, I suggest you first subject them to the five tests to see if they are qualified authorities.  I submit that anyone who asserts that a fat-based carnivorous diet is the best to support human health fails the last test, at least, and that anthropologists and archaeologists are not appropriately qualified authorities on diet, nutrition, or health care (test 3). 

A strong theory of evolution of human diet would be able to explain why vegetarian diets are associated with a lower risk of heart disease than omnivorous diets (as another of many possible examples see this), why vegetarians have a lower body mass index than omnivores, why an essentially vegan soy- and gluten-rich diet reduces cholesterol as effectively as a statin drug, and why eating red meat increases the risk of all cause mortality.  Instead of providing an explanation for these painstakingly established scientific findings, some supporters of the hypothesis that humans evolved as carnivores spend their time trying to explain them away because they don't fit their hypothesis. This is not science, it is anti-science.  A scientist molds his hypotheses to accommodate the facts, not the other way around.

By the way, I wonder if Ben-Dor et al have any idea what hunting elephants entails.  The video below shows primitive spear hunting, including hunting of elephants and hippos.  Knowing the high level of intelligence and sensitivity of elephants (and the other animals as well), I find it appalling.

Thankfully we have evolved and found other ways to sustain ourselves in good health. 

New Post At The Food Way: Meat-free Diet Quickly Improves Mood of Omnivores

When I used the so-called Paleolithic paradigm to guide my approach to nutrition, I embraced the idea that we (humans) have a ‘need’ to eat grass-finished meat and wild fish to get adequate amounts of long-chain omega-3 fatty acids, particularly EPA and DHA, for cardiovascular and neurological health respectively.

Like other supporters of this idea, I believed that lack of animal sources of these fats would cause depression, schizophrenia, attention deficit, and poor intelligence. It all ‘made sense’ based on the hypothesis that meat-eating provided the crucial energy and fatty acids that supported human brain evolution.

After some time I realized this hypothesis ignores the fact that meat provides only fat and protein, while the nervous system prefers glucose. The human brain uses about two-thirds of the glucose used by the entire body. Meat simply does not provide the best fuel for the brain. I now tire of reading anthropologists arguing that meat must have 'fueled' brain expansion because of its rich provision of fats. If they took a moment to study neural cell energy metabolism, they would realize that the expanding human brain needed a steady supply of non-toxic glucose (i.e. glucose not derived from protein), not found in meat or fat.

About eight months ago when preparing my presentation for the Ancestral Health Symposium I recalled that I had previously seen evidence challenging the hypothesis that humans need preformed EPA and DHA for healthy nervous system development and function.

That evidence consisted of studies showing that although vegetarians have essentially no intake of these preformed omega-3 fatty acids, they do not have deficits of  cognitive or neural function. 

Do vegetarian children suffer poor development of intelligence, and do vegetarians in general suffer any disorders that could be attributed to lack of preformed omega-3s?  Read more....

Another Way Eating Meat Makes Us Smarter

Just read Richard Nikoley's Free The Animal post entitled "The Latest Uh-Oh for the Vegetarians and Vegans: Creatine" which refers to a study just published in the British Journal of Nutrition entitled "The influence of creatine supplementation on the cognitive functioning of vegetarians and omnivores."  

Discussions of how a meat-based diet made us smart  by spurring human evolution usually center around meat providing concentrated calories or essential fatty acids.  This new research suggests that the creatine provided by meat also supports better cognitive function among carnivores compared to vegetarians.

According to the abstract of the BJN article:

Young adult females (n 128) were separated into those who were and were not vegetarian. Randomly and under a double-blind procedure, subjects consumed either a placebo or 20 g of creatine supplement for 5 d. Creatine supplementation did not influence measures of verbal fluency and vigilance. However, in vegetarians rather than in those who consume meat, creatine supplementation resulted in better memory. Irrespective of dietary style, the supplementation of creatine decreased the variability in the responses to a choice reaction-time task.

Memory is essential to learning, so we can conclude that a vegetarian supplemented with creatine will learn better than the same vegetarian not supplemented.  But why not just eat meat, an excellent dietary source of creatine?  As Wikipedia points out:

In humans and animals, approximately half of stored creatine originates from food (mainly from meat). Since vegetables do not contain creatine, vegetarians show lower levels of muscle creatine, but show the same levels after using supplements.

So, take a creatine-depleted vegetarian, feed him/her some meat, and voila, now you have a smarter animal.  I have some experience with this.  All my life I have had an exceptionally good memory, so long as I ate meat; but during the time I spent trying to make a vegetarian diet support my health, I had a significant decline in ability to memorize and recall information, obvious not only to me but to people close to me. 

One author reported on this study using the title "Creatine may beef up brain function" in an online journal focusing on supplements.  Apt, but I'd rather see people beef up brain function by eating real food: beef! 


Vegetarians will likely protest that the Institute of Medicine (IOM) does not presently classify creatine as an essential nutrient because human cells can manufacture it from the amino acids arginine, glycine, and methionine.  However, the IOM's  failure to classify a nutrient as essential fact does NOT mean that the nutrient is not essential.  

The history of choline illustrates these points further.  Adolf Strecker discovered choline, a water-soluble nutrient often grouped with B-vitamins, in 1864.  Mammals manufacture some choline using S-adenosylmethionine, derived from the amino acid methionine, as a raw material.  Because of endogenous synthesis, the Institute of Medicine did not classify choline among the essential nutrients until 1998.  


Choline is another nutrient better supplied by meat and especially eggs than by plant foods, and the Wikipedia entry on choline includes this bit:

Strict vegetarians  who avoid all animal products, endurance athletes and people who drink a lot of alcohol may be at risk for choline deficiency  and may benefit from choline supplements.

In general, people who do not eat many whole eggs may have to pay close attention to get enough choline in their diets. Studies on a number of different populations have found that the average intake of choline was below the Adequate Intake (AI).

The body needs choline to manufacture acetylcholine, the primary neurotransmitter, and choline is required for full development of the central nervous system, particularly the memory center of the brain.

Choline deficiency during fetal development affects memory profoundly throughout life.  In  Choline: Critical Role During Fetal Development and Dietary Requirements in Adults Steven Zeisel reports on animal studies of choline deficiency:

Mothers fed choline-deficient diets during late pregnancy have offspring with diminished progenitor cell proliferation and increased apoptosis in fetal hippocampus....and decremented visuospatial and auditory memory.

In contrast, Zeisel reports that although adult rodents decrement in memory as they age, offspring exposed to extra choline in utero do not show this “senility.”

Zeisel also reports on results of studies of choline supplementation in humans.  Among the findings:

In a double-blind study using normal college students, 25 g of phosphatidylcholine caused significant improvement in explicit memory, as measured by a serial learning task; this improvement might have been due to the improved responses of slow learners. A single oral 10 g dose of choline chloride given to normal volunteers significantly decreased the number of trials needed to master a serial-learning word test. The precursor for formation of phosphatidylcholine, cytidine diphosphocholine (CDP-choline), also has been tested for memory-enhancing effects. In a randomized, double-blind, placebo-controlled study, volunteers were treated with 1000 mg/d CDP-choline or placebo for three months. CDP-choline improved immediate and delayed logical memory. In a second study, oral administration of CDP-choline (500−1000 mg/day) for four weeks to elderly subjects with memory deficits but without dementia resulted in improved memory in free recall tasks, but not in recognition tests. In a double-blind study, patients with early Alzheimer-type dementia were treated with 25 g/day phosphatidylcholine for six months. Modest improvements were observed compared with placebo in several memory tests. However, there are studies in which the choline effect on memory was not observed in normal subjects or in patients with dementias.

Given the rather poor track record of supplements, and the fact that humans are evolutionarily adapted to food, not isolated nutrients, I wonder what results these studies would have gotten if instead of using isolated choline chloride or phosphatydylcholine they had simply advised the subjects to eat 3-6 eggs and more than 8 ounces of meat daily.

Stephan blogged about research showing that choline also prevents and reverses non-alcoholic fatty liver disease even in the context of high sugar intake.  Eat egg yolks for a healthy brain and a healthy liver.

These types of findings indicate that humans have long ago adapted to and become dependent upon meat.  If humans did not need meat, they would have the ability to synthesize optimum amounts of creatine and choline in the absence of dietary meat.  Chances are, dietary creatine is as essential to human health as choline or vitamin B-12. 

History suggests we might wait perhaps a century for the Institute of Medicine to decide that creatine is an essential nutrient.   Meanwhile, we have enough evidence:  Humans need meat for optimum health of the nervous system, and the anthropological and experimental evidence already indicates eating meat can literally make you "smarter" than if you don't eat meat.