November 18, 2009

Saying Something Over And Over Doesn't Make It True

No, this is not a post about the "eating fat causes heart disease" fantasy, nor is it a post about Going Rogue, but the issue I am going to discuss here shares features with those topics the Low Carb community has been very resistant to confronting.

The issue is this: The very same people who spend hours hunting through overlooked but well-designed published medical research to provide us gems that help us understand metabolism better seem to lose their respect for scientific method as soon as they turn their attention to theories about human prehistory.

People I otherwise respect greatly accept theories about "paleo diets" and the health of early human populations that are either a) based on a very small sample of outdated early 20th century research or b) entirely made up.

It may come as a surprise to some of you that the study of paleontology is a scientific discipline pursued by intelligent, educated scientists using a wide variety of sophisticated tools. These scientists have come up with many findings that tell us a lot about the lifestyles of real "paleo" peoples around the globe.

None of this research is ever cited by the people who have made the so-called "paleo diet" a religious crusade, people who have never taken the time to look into the evidence these myths are based on.

Paleo Fanatics Show Off Their Ignorance

Just this week I read a post on a Low Carb discussion board claiming that the Egyptian mummy that shows evidence of heart disease came from a period "right after the invention of agriculture"--a statement which in off only by about 11,000 years. Agriculture started somewhere around 12,000 BC and the earliest of these mummies are from about 1600 BC.

By the same token, we know a great deal about the lifestyles of hundreds of modern day hunter gatherers painstakingly collected by trained anthropologists who lived with these people for many years. You would never know this from reading the Paleo fantasist's writings, which invariably cite one and only one source, the early 20th century arctic explorer, Vilhjalmur Stefansson.

A recent correspondent went to far as to inform me, based on what he had read on a Paleo fanatic web site, that Stefansson was the only person to ever live with a hunter gatherer culture while speaking their language. This misstatement ignores the work of at least 400 other trained anthropologists who not only did the exact same thing as Stefansson, living with people of pre-industrial cultures all around the world, but in many cases they lived with these people for far longer than the few winter months Stefansson did. They also published more extensively about their observations in writings intended for other anthropologists, not a popular audience, and those writing later in the century were much more aware of the need to see ALL of what was going on in the culture, rather than cherry pick the cultural details that reinforced their personal beliefs and ignore the rest.

So with this in mind, you can see why I find it disturbing that people with a lot of cred in the Low Carb world, including several of the M.D. mega-bestselling authors, continue to parrot Paleo fantasy statements about "our ancestors' diet" or about the diet and lifestyle of modern non-agricultural peoples that have no more basis in science than the idea that eating fat gives people heart attacks.

What Science Knows About Real Paleo Diet and Lifestyle

If you are interested in learning more about what our ancestors really ate, I would highly recommend a new book written by a brilliant Harvard anthropology professor. It opened my eyes to the advances that have occurred in paleontology since I studied it at the University of Chicago in the 1960s when I took my Anthropology degree there.

The book is Catching Fire: How Cooking Made Us Human by Richard Wrangham.

Wrangham's book's very-well documented thesis is that it was the very early discovery of cooking by pre-human hominids which allowed humans to develop the metabolically expensive human brain. His main point is that cooking, because it breaks down starches and proteins, made redundant the long, metabolically expensive digestive tracts found among pre-human hominids and allowed them to atrophy, freeing up the calories no longer needed for 5 hours a day of chewing and round the clock digesting of raw foods to be used to fuel, and grow, our metabolically expensive brains.

But the relevance of this book to our discussions in the online diet community lies not so much in its primary thesis but in the mass of data, derived from extensive research, the author provides about what the historical and anthropological record tells us about what early humans and prehumans ate.

And that research makes it clear that people and "pre-people" eating pre-agricultural diets bear little relationship to the Supermen described in the Paleo Myth invented people ignorant of paleontology and anthropology.

For starters, in most of the many modern era hunter-gatherer societies studied since the late 19th century, it turns out that at least 50% of calories came from gathered, i.e. vegetable, sources not meat, almost always provided by females. And even more importantly, these gathered foods were not made up of leaves which provide very little nutrition, but of starchy foods especially roots, seeds, and tubers.

Wrangham also cites the finding that the Inuit, so beloved by Paleo fantasists, ate more than fat and meat: they savored the raw, full intestines of their prey as well as deer droppings. This suggests the lengths to which humans will go to get the nutrients found from plant-derived sources--and how inadvisable it is to use the Inuit as the model upon which to base your diet.

Nor does research substantiate the idea that the lives of ancient Paleo people were the easy, physically invigorating idylls the Paleo myth describes. Hunting in most environments is an exhausting pursuit that provides marginal sustenance. The usual prey is not an elephant but a few small rodents. In most modern era pre-agricultural societies the sheer volume of food-related labor women are forced to provide is comparable with what was demanded of plantation slaves or the most oppressed factory worker.

The fantasy is that Paleo people lived lives of unparalleled health until they were forced into agriculture and made to live on evil carbs. The reality is that the bones of our "paleo" ancestors show clear signs that they were subject to periodic, severe and crippling famines.

This finding is, of course, reinforced by reports from those who had first contact with modern era hunter gatherers. It is often forgotten that one of the reasons that the earliest French settlers of Canada had so much contact with Native American tribes is that the tribes were starving when Champlain first encountered them, and they came to the French because they offered food.

Wrangham also points out that in modern Africa traditional people's must contend with a long period during the Dry Season when famine is common when game disappears.

I recently read a fascinating biography of a 19th century white child who was raised by Californian Native Americans living a traditional lifestyle, The Blue Tattoo: The Life of Olive Oatman (Women in the West) which made clear what it would be like to live through such a periodic famine. It describes one that occurred in a traditional non-contact Native American society living in SE California. Summary: many children died as did many older adults.

People adopted agriculture because it gave them a much better chance of seeing their children survive. Women probably put a lot of pressure on their men to adopt the agricultural lifestyle because as hard as women work in agricultural societies, their lot in them is far better than those of women in pre-agricultural societies who may have to gather and drag 30 lbs of roots over a range of ten or more miles every single day--before they start cooking dinner for men just returned from hunting.

It is worth remembering that those very few pre-agricultural societies that survived the agricultural revolution--the ones observed by Stefansson and others--were all cultures where people lived in environments where hunting and gathering provided more food than agriculture could--areas with very short (or in the arctic, no) growing seasons, deserts, areas with disease vectors that made settled life fatal, or very rarely, as in Amazonia and New Guinea, tropical areas where nature provided much more food than it does in the temperate zones.

Everywhere else, hunting and gathering was a very hard way to stay alive, and people took to agriculture with the alacrity with which our generation has taken to the computer and for the same reason: because the benefits were undeniable and instantly obvious.

Grain-based agriculture let more children survive to adulthood. Only after its advent did the human population begin to grow at a steady rate, rather than just barely replacing itself.

Grain-based agriculture provides, uniquely in human experience, enough surplus food that some people can put their time into non-calorie producing behaviors, like inventing writing which allows shared knowledge and technology to grow beyond what one person can retain in their memory. It is those grain-provided surplusses that have led to your being able to sit in front of your computer reading this post even if you do it while imagining how much happier you would be if you were "Paleo Man."

Why Does It Matter?

Okay, you might say, maybe the whole Paleo thing is a myth, but why make a big deal about it?

The answer is simple. The minute you support a good idea with made up "facts" and bad science, you invalidate it.

Doctors and nutritionists ignored the Atkins diet because he supported his claims with outdated, discredited studies like the one describing "fat mobilizing substance" and the research that claimed someone lost a huge amount of weight eating ten thousand calories a day of fat. By relying on bad science (and not updating the books to remove it, long after it was known to be bad science) Atkins delayed for a generation the rigorous study of the low carb diet.

We run the risk of doing the same thing to the diet when we argue for it using myths that educated people know to be myths.

What makes it so sad is that there is no need to use myths to make our point. There is plenty of very good science that supports the advantage of cutting down on carbs, eliminating processed foods, and demanding that industry stop polluting our environment with organic chemicals that are damaging our bodies We don't need to argue for our modern dietary improvements by citing imaginary, Eden-dwelling ancestors and misrepresenting their diets to do it.

The truth is, it is irrelevant what ancient people ate 20,000 years ago. Evolution occurs in periods as short as 100 years, so the dietary changes that have taken place in that past 20,000 years have altered our metabolic physiology in thousands of small ways that make us very different physiologically from "paleo" people.

To see an example of this, we need only remember that those of us who are descended from herders can digest milk as adults, while those who did not evolve in cultures with domesticated milk-giving animals are lactose intolerant, like most other adult mammals.

So matter what Paleo peoples ate, those of us who descend from European or Asian stock living in the Temperate Zone can be sure our ancestors' bodies adapted very well to agricultural diets. We are all descended from people who flourished on the energy provided by the stored starchy vegetables and grains that kept them alive through the long cold northern winters when game is very hard to find. Those who did not flourish on those diets did not survive to become anyone's ancestors.

It's Not The Deep Past But The Very Recent Past That Points to The Problems

Rather than imagining the far distant past, we need only look at the very recent past to find much more relevant arguments to support our need for dietary change.

It is the new factors introduced in the past century that we should be focussing the full force of Science on to answer the question of why we have a sudden epidemic of metabolic diseases. Research is turning up a lot of answers, though the corporate-owned media ignore those that point to corporate culpability as the explanation.

The obesity/diabetes epidemic is closely related to the phthalates and other organic molecules that leach from PVC plastics and Bisphenol-A that estrogenize our bodies, the soy proteins that damage our gut linings allowing otherwise benign gluten to get into our blood stream an provoke autoimmune attack, the high fructose corn syrup that turns into intracellular liver fat, the arsenic from coal burning that promotes diabetes, the PCB, pesticide, herbicide and pharmaceutical drugs that are in our water supply and our bodies which all increase insulin resistance.

Let's focus on the real science and make the public aware of the findings of this good science so we can do something about this metabolic epidemic. Until we can heal it, those of us who can't process carbs will have to cut way back on them. But let's leave the myths that reinforce personal belief systems to the churches where they belong. They won't cure what ails us.
=====
UPDATE: Nov 21, 2009:

Check out this fascinating look at Arctic mummies. The link was posted by "Coach Jeff" in the comment section. The book cited is a real eye opener. I will have go get a copy.

Mummies, disease & ancient cultures By Eve Cockburn, Theodore Allen Reyman

Two of the Arctic and Aleutian mummies described here--those of older people--show distinct signs of atherosclerosis. The starved child who died with a tummy full of gravel and hair points out the impact of cyclical starvation on hunter cultures.



 

37 comments:

RLL said...

Jenny - you probably have the contacts to confirm/clarify this useful fact about human evolution. I read, in a book that was connecting much human disease (don't remember author, title), that a 1% advantage in the human gene population will become predominate in about 1000 years.

ps - as always this was a useful read

pps - Ben Franklin commented that Europeans, men or women, who were captured/other and lived with tribes were always reluctant/unwilling to return to European civilization. Tribal life has a real siren call.

Charles R. said...

While I think some of what you say has merit, I think you paint with much too broad a brush.

In particular, to say that the only source cited is Steffansson is just not correct. As is saying that none of the paleo dietary precepts are based on any real science.

One of the first, if not the first, scientist to come up with the paleo concept is Loren Cordain, who has written a number of respectable, published papers. Here's a listing of his research:

http://www.thepaleodiet.com/published_research/

Just because there are idiots who approach the subject as religion more than science, it's unfair and inaccurate to portray the entire movement that way. That's as anecdotal and unscientific as those you criticize.

Anna said...

I'm halfway through reading Wragham's Catching Fire and it is indeed a very good book.

PJNOIR said...

I never like the caveman analogy. No way could we duplicate their conditions, lifestyle or food source. I do enjoy intermitting fasting as long as it isn't on a schedule. And I have followed Atkins with clean grass fed beef with GREAT results controlling by diabetes. The bottom line is to add more Lipids to the diet. lower modern carbs, and avoid grains, especially those turned to flour. As always Jen-a great post, just be careful of modern cavefolk (LOL)

Gretchen said...

I agree with you that some of the diet writers have an idealized, most likely inaccurate view of hunther/gatherer societies.

One author said that the human digestive system is designed for people who starve for days and then hunt down some enormous animal and gorge on it. I just finished a book by a guy who lived among Eskimos/Inuit in the 1930s. They were quite aware that winter was long, so they did a lot of hunting when they could and cached their food (easy when it freezes) so in good years they had a constant supply of meat.

Seal hunting was easier in winter, as the seals had to surface at their air holes to breathe.

Other groups in warmer places dried their protein sources.

The idea that they ate the intestinal contents is also not quite true. Some groups did. Others, including this group (Hudson Bay area) fed the intestines and contents to the dogs.

I think we'll never really how how the "average" Paleolithic hunter lived, and there were undoubtedly as many variations then as there are today, depending in part on climate.

I think whether or not grain growers were better off than hunter/gatherers depends on whether the grain raisers ended up being Pharaohs or the poor slobs who toiled in the fields supporting them and their fancy writing, much of which evolved to keep track of taxes due.

Good blogpost!

Helen said...

Rock on, Jenny. I've been wanting to read "Catching Fire," and I also have questioned the assumptions made about Paleolithic peoples' diets by people following a modern Paleo diet.

They seem to assume "big game" was the main calorie source, but this goes against what I learned about hunter-gatherers in my two anthropology classes and other reading. (I'm also the daughter of two anthropologists, though I'm not sure that's schooled me any in this subject.)

It also goes against simple thought experiments about the foods available in the widely varying regions that humans have lived in. In some, there is a fair amount of fruit, in some, a lot of fish, in some, small, medium, and large game. Claims are made that fruit is seasonal and therefore wasn't a big part of our ancestral diet. Indeed, fruit is seasonal, *and so is game.*

On the North American west coast, people collected acorns and processed them to remove the tannins. In the Southwest, some native people still eat gathered pine nuts as a staple.

Also, humans used to eat more bugs. I am still waiting for that one to hit the health food stores. They contain vitamin K2 and probably have some other health benefits.

Another thing to consider is that hunter-gatherers intentionally kept their populations small so as not to outstrip their food resources. I'm not sure the food-gathering was always as arduous as you state, or agriculture as liberating from famine or the daily grind, but it did enable humans to increase their environment's "carrying capacity." (It also augured a more patriarchal, class-stratified society.)

I do think humans have adapted somewhat to the changes in diet that came from the rise of herding and of settled agriculture.

But I'm not sure we've *totally* adapted to eating grains. I do think that our ancestors figured out how to process them to get the most good out of them with the least harm (through soaking and fermentation), a la Weston A. Price's observations.

Modern food preparation that throws these techniques out the window, the addition of soy to everything (among other substances), along with all these terrible chemicals, and the admonition to cut saturated fat and fill up on bread and pasta, have led to our current fix.

Susan said...

I've been round and round with the Paleoists over the issue of H. erectus cooking and tubers. I've also quoted extensively from texts on the Hadza and !Kung and it didn't do a bit of good.

Boyd Eaton put the idea of the paleolithic diet into the scientific literature and he is roundly ridiculed by the low carb paelo mob. None of the followers of Cordain or the latest PaNu site have a clue about real anthropology.

Matt Stone said...

You mean humans are omnivores? We ate something besides wooly mammoth T-bones prior to last week?

Jenny, this is an absolutely amazing post. Thanks for having the mental flexibility to get out from underneath such low-carb/Paleo nonsense. Best blog post I've read in months.

Humans only eat zero carb diets when they have access to zero carbs. Sure, we can be healthy on a multitude of diets, but the Eskimo were the exception, not the rule.

LynMarie Daye said...

Jenny - I may have read you wrong, but are you suggesting that Stefansson cherry-picked the cultural details he put in his writings for the lay public? I'm not arguing with that contention as I have no idea one way or the other; I'm just trying to understand better.

I have to say I find it interesting how Stefansson's writings are seen as the final authority for *some* in the paleo-diet world. Recently on a zero carb forum, someone posted that he had just read "Catching Fire" and while he got a lot out of it, he was somewhat distressed to see that Wrangham believes that Native Americans often put acidic fruits in their pemmican. Another poster responded with: "I rolled my eyes at that one. Wrangham obviously failed to read "Not By Bread Alone." I doubt very much that Wrangham has never read NBBA. Most likely, he read it along with a lot of other writings/studies and came to a different conclusion. Why didn't the poster express interest in finding out why Wrangham believes what he does regarding pemmican? Well, IMO, it's because her dietary beliefs are based, not on science, but on something more akin to a religion.

Thanks for reminding me about "Catching Fire". I remember hearing about it and planned to get a copy, but then it slipped my mind. I hope I get it in time for my 700 mile car trip next week. My husband will be driving and I will be reading! ;`)

Jenny said...

LynnMarie,

Books written for a popular audience have to provide a different kind of read than a scholarly work. I'm not saying there isn't value in Stefansson's writing, only that he is not the final authority on Inuit culture and that the writings of others who have study them tell us things he left out.

And yes, the problem is that Paleo has become a religious belief that like many harks back to the idea of an Eden state that we collectively lost through Sin. In this case, the sin is redefined as being dietary.

But once diet becomes a matter of religion, whatever diet is involved, it becomes very difficult to get people to look at facts that might challenge their beliefs.

If people are currently earning a living by promoting those beliefs it becomes impossible. The person who has been pushing a theory on patients or follower who learns something new might have to face the possibility he or she has been harming, not helping.

Most people would rather continue giving bad or dangerous "aid" than admit they've been hurting people.

Paradoxical.

Kurt G. Harris MD said...

@Susan

You said:

"None of the followers of Cordain or the latest PaNu site have a clue about real anthropology."

You have obviously not read much of my site if you lump me with Cordain. I have been critical of Cordain, stated repeatedly that I think paleolithic food read enactment is impossible, and I have spent little time speculating on the exact diet of paleolithic humans. I have some followers among zero-carbers and other paleofantasists, but I fight with them constantly over whether plants and carbs are "poison". (Hint- I say they are not). I do think its obvious plants are more optional than animals in our diets.

I read wrangham's book 6 months ago, reviewed it and I link to it.

I also consume and promote dairy.

I have to assume you are referring to one of my commenters or you have never read much of my site.

Jenny makes some good points but is wrong about us being adapted to cereal grains, however.

Susan said...

@Dr. Harris,

Sorry, I wasn't talking about you nor Dr. Cordain, but people who have adopted the paleo plans and have basically subverted them to their own beliefs. One of them was a fundamentalist Christan who believes the earth is only 40,000 years old, yet he eats what he thinks is "paleo."

Gyan said...

The claim that hunters-gatherers intentionally limited populatize size is popular but is there any actual evidence for it?
It seems biologically peculiar. Do animals do it?> And how does it actually mean?
Contience or infanticide?

Jenny said...

Each human hunter gatherer culture studied has its own cultural peculiarities. You can't say "ALL" in reference to habits. Many expose a second twin to die, some don't, for example, because it is so hard to successfully nurse even one child living that way.

The only voluntary way of limiting population I've ever read about in such cultures is demand nursing. When you carry a baby and nurse it continually it will usually but not always suppress ovulation.

The other way of course is starvation. Reduce a woman's fat stores below a certain point or overexercise her and she will stop ovulating too.

Radhakrishna said...

Thanks Jenny for this nice article. I agree with you on most of what you say but have to slightly disagree with the following: " No matter what Paleo peoples ate, those of us who descend from European or Asian stock living in the Temperate Zone can be sure our ancestors' bodies adapted very well to agricultural diets. We are all descended from people who flourished on the energy provided by the stored starchy vegetables and grains that kept them alive through the long cold northern winters when game is very hard to find. " Not just 'temperate zone', Jenny. More than 20% of world's population live in the Indian subcontinent (that is, India, Pakistan, Bangladesh, etc.) These people have descended from those ancestors of ours who took to agriculture from perhaps day one of its 'discovery'. And these people, and their ancestors, did not live in temperate climate; they lived in tropical and subtropical climate although the land they lived in may happen to be north of the Tropic of Cancer (23.5 deg N latitude.) The tall Himalayas protect these lands from the relatively colder temperate climate. Hence these people did not have to live through 'cold northern winters' when food become scarce. Food was relatively plentiful because their diet was (and is) predominantly plant based food and a large number among them could (and continue to do so to the present) choose to live only on plant based food (with the exception of milk products because these people are lacto vegetarians.)

Regards,
Rad

Ukay Bukit said...

Interesting to mention the Hadza of Tanzania Great Rift Valley.

The December 2009 National Geographic has a piece on the Hadza that give a very different picture of hunter gathering than you get at the paleo sites, especially the ketogenic ones. Very eye-opening.

The Hadza typically spend 4 to 6 hours daily obtaining food, the men hunt a wide variety of game, the women gather baobab fruit

Charles R. said...

Well yes, it's possible to live mainly on starchy carbohydrates and plant foods, but that doesn't mean that's the optimum diet.

All that evolution needs you to do is get to child-bearing age and have children. After that, it doesn't really matter if you have heart disease, diabetes or whatever.

And south Asia has one of the highest heart disease rates of anywhere in the world, despite their vegetarianism.

So "adapt" may be one thing, but "thrive" is another. And when we equate adapting with simple survival, I think that confuses the issue.

I guess I'm having a hard time accepting that our ancestors "adapted well to agricultural diets." I just don't see the evidence for that. And increased reproduction is not evidence of adapting well.

Susan said...

@Ukay - The Hadza are one of the most interesting pre-agricultural tribes I studied in college. Majorie Shostak's ethnological expose of the fictionally named Hadza woman Nisa is one of the best reads in anthropology.

She co-authored "The Paleolithic Prescription" with Boyd Eaton which presents a very different view of a paleo diet.

canladdie said...

Well-done, especially your core argument about the Paleo fallacies, and the need to focus on current knowledge. Thanks!

Radhakrishna said...

Charles R. wrote:

"And south Asia has one of the highest heart disease rates of anywhere in the world, despite their vegetarianism."

I don't think vegetarianism or predominance of plant based food is the reason why south
Asia has higher incidence of heart disease or diabetes. It is just that natural selection did not operate there as effectively as it did in the harsher climates of Europe and other places to weed out 'unfit' genes. The land yielded relatively plentiful food, and the climate did not challenge the body to the extent that it did in the harsher climes where Man had to wage a relentless war against nature just to barely survive. So the 'less fit' genes were not weeded out as they were in harsher climes. In Europe, I am told that the incidence of diabetes is higher in the milder climates of southern Europe than in the harsher climate of northern Europe. Again, it looks like natural selection is more effective in harsher environments.

So "adapt" may be one thing, but "thrive" is another. And when we equate adapting with simple survival, I think that confuses the issue .

What is the definition of 'thrive'? If it means living more number of years, build up sophisticated civilizations, and cause the blossoming of art, literature, philosophy and scientific thinking, I think societies in the milder climates who depended more on plant food and agriculture did indeed much better than the others. (A brief period of exception is the modern, exploitative period of colonial rule.) Even within Europe, civilization developed in the milder south long before it reached the harsher north.

All people in south Asia are not diabetics or suffer heart problems. The percentage of diabetics and those with heart disease in the total population is still a small number even if it happens to be a little higher than elsewhere. It means that the society as a whole did well in adapting to an agricultural diet, but the relative abundance of food and the milder climate allowed more individuals with 'unfit' genes to thrive. Natural selection was not just as effective as in the harsher 'temperate' climates of the north.

This is just my humble opinion.

Regards,
Rad

Coach Jeff said...

Great post...regarding the notion that Arctic dwellers enjoyed perfect health due to an all-meat diet...well they've actually studies Arctic mummies (Yes, there is such a thing) and find that they DID have some health issues on their very low-carb diets.

http://books.google.com/books?hl=en&lr=&id=5a7TP57S1GkC&oi=fnd&pg=PA138&dq=eskimo+mummies&ots=W9RV09Uw68&sig=XqlIIdVlCau3c8kxYnO7z-WXBcw#v=onepage&q=eskimo%20mummies&f=false

O Primitivo said...

"Primitive times are lyrical, ancient times epical, modern times dramatic." (Victor Hugo, 1827)

Richard Nikoley said...

Jenny:

I think the central theme of what I get out of your post has good merit.

What was once a very valid, scientifically based hypothesis, i.e., "Paleo," as espoused by Cordain and other is being co-opted by many to provide a foundation for their specific dietary prescriptions.

My paleo approach is different. I have repeatedly written that "paleo" includes everything between the extremes of a Kitavan diet of 70% natural carbs and an Inuit diet of 80% natural fats. I doubt either is optimal and that optimal must be discovered INDIVIDUALLY, somewhere between those extremes and is likely going to have something to do with where your ancestors came from. Did they evolve in the tropics, survive an ice age, where they among the first to begin the development of agriculture.

For me, both parents' ancestors come from N Europe and so it's no surprise that a high-animal-fat diet works well for me, and I've lost 60 pounds on it.

My wife's ancestors are from Mexico. She doesn't respond the same way individually to high fat and tolerates carbs way better than me.

For me, paleo principally means avoiding processed food. Eat real food only, source and prepare most of it yourself, and discover for yourself what works best for you.

Jenny said...

Richard,

Your concept sounds very reasonable. But we can't read too much into ethnic background.

My own mother can eat anything and get a perfectly normal blood sugar. So can my son. I can't, nor can my daughter.

A single point mutation on an important gene can make a big difference in how you process glucose. And the mutation can be acquired, not just transmitted by birth the way ours seems to have been.

We live in an environment rich in chemical pollutants that apear to be able to modify gene expression both in the developing fetus and, in the case of herbicides, pesticides, etc, later in life.

For some of us the genetic damage means even the most perfect diet is not going to be enough to surmount the problems.

pjnoir said...

Going back and reviewing some of the paleo web sites, it is clear to see that most cherry pick their science facts about caveman diet. And live to the word of other science, as long as facts don't get in the way of a good post or blog. But Dr. Harris is a good one to read- I love his post about their being no single magic food- rates right up their with your stuff. Still once I stopped eating grains (wheat and its flour, corn and its meal and rice) and added good fat from coconuts and animal to my diet, my faulty metabolism is starting act regular. Happy Thanksgiving Jen - can't wait til you get back with a post. Thanks for firing a salvo over the bow of the paleo canoes.

LynMarie Daye said...

Coach Jeff - I've had that book (Mummies, Disease and Ancient Cultures) for several years. The point that stood out to me most, as a woman, is the extensive bone demineralization that was found in the female Alaskan mummies. One mummy was determined to be in her mid-20's at the time of death, yet had significant bone mineral loss. I have no doubt that Inuit on their traditional diets enjoyed general good health, but it certainly wasn't perfect.

Jim Purdy said...

"Wrangham's book's very-well documented thesis is that it was the very early discovery of cooking by pre-human hominids which allowed humans to develop the metabolically expensive human brain. His main point is that cooking, because it breaks down starches and proteins, made redundant the long, metabolically expensive digestive tracts found among pre-human hominids and allowed them to atrophy, freeing up the calories no longer needed for 5 hours a day of chewing and round the clock digesting of raw foods to be used to fuel, and grow, our metabolically expensive brains. "

Uh, okay, but all that seems to show is that cooking may have led to bigger brains and shorter digestive tracts. But bigger brains don't necessarily mean smarter or faster. If it did, a tiny fruit fly wouldn't be able to so easily avoid my swats.

And if cooked food made for bigger brains, why didn't domesticated cats and dogs that shared our cooked scraps evolve big brains?

Could it be that is was the ACT of cooking, rather than the cooked food itself, that led to intelligent human skills, like language? While paleo-men went out to club, stone or spear each other and their prey, the women stayed home and learned how to cook the food and care for the young.

And the presence of women in groups probably had much more to do with developing reasoning and language than the testosterone-induced grunts and shouts of the hunters.

Okay, I plead guilty. I'm just speculating on gender roles, but I don't think we have very enough knowledge to say that cooked food led to what we are today.

Jenny said...

Jim,

Read the book. It is not one I can do justice to in a few paragraphs.
He addresses your points.

Anna said...

Dogs became domesticated in about 15,000 BC; cats did not become domesticated until the adoption of agriculture (common estimates are about 7500 BC, though skeletal remains of a cat were found with human remains that date to about 9500 BC). Cats became domesticated primarily because of their rodent hunting skills, which was useful with the production and accumulation of grain. Unlike dogs, domesticated cats have few other skills that benefit humans besides rodent predation and companionship. It may be that cats were drawn to the vermin-infested grain stores and humans merely capitalized on the symbiotic relationship.

Nigel Kinbrum BSc(Hons)Eng said...

We domesticated dogs.
Cats domesticated us! ;-)

Gyan said...

Jenny,
Demand nursing may stop ovulation but it is a far thing to say that women practice(d) demand nursing to intentionally limit family size.

Coach Jeff said...

LynMarie Daye - Yes I remember that as well about the bone demineralization in the young female mummy. Perhaps partly due to lack of calcium or magnesium. Or perhaps due to lack of alkaline vegetation to buffer the net acid load of their carnivorous diet.

And of course even Steffanson himself commented on how badly they aged.

I find myself leaning more and more toward the S Boyd Eaton school of paleolithic thought these days. Though, like Janet and Matt Stone, I am NOT convinced that grains are the de-facto dietary menace they're portrayed as by many.

Though I am intrigued by the idea that lectins may cause hyperhagia.

Janet, what to you think of the theory that wheat lectins can bind to leptin receptors, and make your brain "blind" to leptin, which then leads to hyperphagia?

Danny Jimmy said...

The research on phthalate is pretty bad as there's no such a thing as gender-specific behaviors, they're created and invented bu society and culture.

Truck or soldiers toys are just an invention, a social construction that has no link with physiology or development.

Humans are too complex to be divided into typical superficial binary of western thinking, let alone using such fake constructed binaries to make scientific conclusions about health.

Jim Purdy said...

Danny Jimmy said:
"... there's no such a thing as gender-specific behaviors, they're created and invented bu society and culture."

That is an amazingly broad generalization, made even more striking by the fact that it follows Jenny's post which cited gender differences in early societies. If the gender differences are invented, then why are they so widespread across cultures and even across species?

I'm wondering if Jenny and Danny Jimmy have any common ground, or is this a big difference of opinion? I suspect that the truth is somewhere in between.

Neonomide said...

@Danny Jimmy,

I'm a gender studies major and frankly I think there is no evidence to claim that gender differences are culture derived only. There exists a psychobiological component and it's strong.

Modern sosiology professors still need to cite Margaret Mead and her never-replicated studies of a few cultures that had inverse gender roles to justify their position - which is that gender is not biological. Otherwise modern sociology could not exist as it is. When the evidence remains as sparse as this, it's amazing how long even the most educated people can keep on fooling students and perhaps(?) themselfs.

Jenny,

Wrangham remains much critizised for his machismo driven research on chimpanzee warfare and "demonic males" and did work witrh Jane Goodall. I wouldn't drink everythink he boils, but thanks I'll check the book anyway.

By the way, you critique of paleo hizbollah fits IMO better with ideologically driven ZC:s than the majority of paleos I know. But then, harsh counter tales are a fun way to make points clear, of course. ^^

doctor_ostric said...

Have you read "where good ideas come from?" by Steven Johnson? It talks about the benefits of having cities, etc. which you mention. Although the theory of geographical luck and the inequality of grain is a very powerful thesis, I too have a lot of problems with 'paleo.' I loved the book how fire made us human, but in Micheal Pollan's book, the Omnivore's Dilemma, he talks about mushrooms being the reason our brains grew. The fact is we really don't know what the answers are, and I share your concern that the integrity of the scientific debate is sometimes diluted with catch-phrases. That being said, I think paleo has done a lot of good things by bringing awareness about what exactly we are and where we come from. It is a great post. You would do well to read that Steven Johnson book, as it is not in the Paleo-library, which of course, wouldn't have existed either without grains! You have to have a sense humor too...sometimes people are way to serious about all this.

Jenny said...

You certainly are right about the need for a sense of humor when approaching any web-based diet discussion!