“The important thing in science is not so much to obtain new facts as to discover new ways of thinking about them.” — William Bragg
The following short article came over the transit, as it were, a couple of days ago. Shot to me by a friend who knew it’d make my eyes roll. It’s a piece that is, while not completely disparaging, is at least smugly dismissive of the Paleo diet. And while “dissin’ Paleo” is nothing new, this particular piece caught my attention because (1) it concisely encapsulates what I consider to be the most common (purposely perpetuated by the establishment) misconceptions of the diet, (2) it appeared in a rather prestigious publication (Scientific American), and (3) of who wrote it.
Here’s the article:
From the standpoint of paleoecology, the so-called Paleo diet is a myth
First off, I have all the respect in the world for Peter Ungar, who is Distinguished Professor, and director of the Environmental Dynamics Program at the University of Arkansas. He’s also the author of Evolution’s Bite: A Story of Teeth, Diet, and Human Origins.
And so this is not meant to be an ad hominem, character assassination or blind side. I totally understand the frustration of having space limitations and word count not allow you fully flesh out your ideas. But I do think Peter illuminates and clearly articulates some of the common misconceptions of what this Paleo movement — and it is a movement — is all about.
I’ve reprinted the article here, in italics, with my comments in regular print.
And I’d love to hear your thoughts in the comments section.
Strap in tight; here we go.
The “True” Human Diet
From the standpoint of paleoecology, the so-called Paleo diet is a myth
People have been debating the natural human diet for thousands of years, often framed as a question of the morality of eating other animals. The lion has no choice, but we do. Take the ancient Greek philosopher Pythagoras, for example: “Oh, how wrong it is for flesh to be made from flesh!” The argument hasn’t changed much for ethical vegetarians in 2,500 years, but today we also have Sarah Palin, who wrote in Going Rogue: An American Life, “If God had not intended for us to eat animals, how come He made them out of meat?” Have a look at Genesis 9:3.
So I’m put on guard immediately; the oldest trick in the bag of sound-bite debate: the parade of freaks. Want to quickly discredit the other side? Spotlight the lunatic fringe. Looking to slam religion? March out the fundamentalists and radicals. The second oldest trick in the debate (or info /”false news” wars) used by the establishment (or those who “have something to lose” by a culturally held belief being disproven) is to simply cast doubt on the other side. You “win” i.e., keep your job, your “subject matter expert” status, or keep your business afloat long enough to see you though. For more on that, check out the fabulous documentary “Merchants of Doubt”. See the clip below:
While humans don’t have the teeth or claws of a mammal evolved to kill and eat other animals, that doesn’t mean we aren’t “supposed” to eat meat, though. Our early Homo ancestors invented weapons and cutting tools in lieu of sharp carnivore-like teeth. There’s no explanation other than meat eating for the fossil animal bones riddled with stone tool cut marks at fossil sites. It also explains our simple guts, which look little like those evolved to process large quantities of fibrous plant foods.
And in addition to being (so far as we know) the only life here on earth conscious of its own consciousness, we have these awesome opposable thumbs. And an intelligence that would enable us to harness fire, which is, of course, a mechanism that enabled our species to trade (relative to our overall size), guts for additional brain power. And, too, the harnessing of fire is just one example of our species’ greatest trump card: adaptability.
But gluten isn’t unnatural either. Despite the pervasive call to cut carbs, there’s plenty of evidence that cereal grains were staples, at least for some, long before domestication. People at Ohalo II on the shore of the Sea of Galilee ate wheat and barley during the peak of the last ice age, more than 10,000 years before these grains were domesticated. Paleobotanists have even found starch granules trapped in the tartar on 40,000-year-old Neandertal teeth with the distinctive shapes of barley and other grains, and the telltale damage that comes from cooking. There’s nothing new about cereal consumption.
As always, the poison is in the dose. Also see optimum foraging theory. We evolved as “obligate movers and opportunistic eaters”. That means we preferred fats, but ate pretty much anything we could shove down our pie-holes that (a) didn’t kill us first, or (b) wouldn’t kill us soon after with a lethal dose of poisons. The problem here — as it pertains specifically to gluten — is that it’s both ubiquitous in our modern environment, mega dosed as packaged in hyper-palatable foods, and (as an unintended consequence of genetic manipulation) present in much higher concentrations per unit of milled grain.
We have to compare apples to apples here — availability, dose and frequency of consumption. I’d also argue the word “staple”, which implies “that which is most commonly utilized”. Clearly our gut structure and the availability of such grains make it impossible via-a-vis our fat, nutrient density (of which grains are wholly lacking) and overall metabolic requirements to define grains as a “staple” of our species.
This leads us to the Paleolithic Diet. As a paleoanthropologist I’m often asked for my thoughts about it. I’m not really a fan—I like pizza and French fries and ice cream too much.
“Ubiquitous in the modern environment” and “hyper-palatability” anyone? It’s a joke; I get it. And yet, there is much truth here. People are apt to mightily defend what they take comfort in and from. Bias noted.
Nevertheless, diet gurus have built a strong case for discordance between what we eat today and what our ancestors evolved to eat. The idea is that our diets have changed too quickly for our genes to keep up; and the result is said to be “metabolic syndrome,” a cluster of conditions including elevated blood pressure, high blood-sugar level, obesity, and abnormal cholesterol levels. It’s a compelling argument. Think about what might happen if you put diesel in an automobile built for regular gasoline. The wrong fuel can wreak havoc on the system, whether you’re filling a car or stuffing your face.
I don’t know how much more compelling an argument there can be, other than the legions of personal evidence we have of what eliminating these foods can do for the reversal of these diseases. Do we really need randomized controlled studies to tell us that parachutes are highly effective for their intended purpose? Or can we simply say that the proof is in the (gluten-free, made of avocado) pudding? Citizen science, #ftw.
It makes sense, and it’s no surprise that Paleolithic diets remain hugely popular.
Uhhhhh… because they work, where all other diet and lifestyle changes do not? It’s as if defenders of the status quo are saying “are you going to believe me, or your lying eyes?”
There are many variants on the general theme, but foods rich in protein and omega-3 fatty acids show up again and again. Grass-fed cow meat and fish are good, and carbohydrates should come from nonstarchy fresh fruits and vegetables. On the other hand, cereal grains, legumes, dairy, potatoes, and highly refined and processed foods are out. The idea is to eat like our Stone Age ancestors—you know, spinach salads with avocado, walnuts, diced turkey, and the like.
Yeah, we get it. Cavemen didn’t have access to culinary finery. We can yuck it up all the way to the next dialysis treatment. But part and parcel to that big brain and spectacular adaptability comes the ability to navigate nuance. Threading the needle of directional accuracy, as it were. I guess we’ll just wait for a peer-reviewed, scientific study on this. Until then, let’s continue on with the Standard American Diet. At least that one has some (riddled with holes) studies behind it. And (as we’ll see later) it’s accurately named. That makes me feel better.
I am not a dietician, and cannot speak with authority about the nutritional costs and benefits of Paleolithic diets, but I can comment on their evolutionary underpinnings. From the standpoint of paleoecology, the Paleolithic diet is a myth.
This argument continues to absolutely befuddle me. It’s is akin to someone refusing to perform Russian leg curls or Romanian deadlifts because, well, it was actually the Bulgarians who first described each of those moves. Intellectual masturbation is no doubt cute, but it does nothing to change lives.
That said, we can continue to argue nomenclature and semantics of naming a diet while the disease rates in this country skyrocket and the economy crumbles because of it. Because, well, the Standard American Diet is pretty much… standard nomenclature. Nevermind the fact that it’s laden with “standard” foods that make people sick and fat (and that are, by the way, government subsidized). Creating the underpinnings for the American medical-pharma-insurance industrial complex. But I get it: “standard” implies “ubiquitous”, which is pretty much where we are with diet-driven disease in this country.
Food choice is as much about what’s available to be eaten as it is about what a species evolved to eat. And just as fruits ripen, leaves flush, and flowers bloom predictably at different times of the year, foods available to our ancestors varied over deep time as the world changed around them from warm and wet to cool and dry and back again. Those changes are what drove our evolution.
Yes, we evolved as obligate movers and opportunistic eaters. The flip-side being that we, as a species, and for survival necessity, are hardwired for laziness and gluttony. Which worked in (and in conjunction with) our evolutionary crucible. Because to be wired otherwise (picky eaters and frivolous energy expenders) would lead to the demise of our species.
Even if we could reconstruct the precise nutrient composition of foods eaten by a particular hominin species in the past (and we can’t), the information would be meaningless for planning a menu based on our ancestral diet. Because our world was ever changing, so too was the diet of our ancestors. Focusing on a single point in our evolution would be futile. We’re a work in progress. Hominins were spread over space too, and those living in the forest by the river surely had a different diet from their cousins on the lakeshore or the open savanna.
How hard is it to understand “environmental mismatch”? And “directional accuracy”? No, we’ll never again be able to eat wooly mammoth. But does that then we should subsist on Pop-Tarts and Twinkies (or the author’s pizza and ice cream) because that’s what our modern society has made ubiquitous? Are we so stupid as to not be able to study, best approximate, test and evaluate?
What was the ancestral human diet? The question itself makes no sense. Consider some of the recent hunter-gatherers who have inspired Paleolithic diet enthusiasts. The Tikiġaġmiut of the north Alaskan coast lived almost entirely on the protein and fat of marine mammals and fish, while the Gwi San in Botswana’s Central Kalahari took something like 70 percent of their calories from carbohydrate-rich, sugary melons and starchy roots. Traditional human foragers managed to earn a living from the larger community of life that surrounded them in a remarkable variety of habitats, from near-polar latitudes to the tropics. Few other mammalian species can make that claim, and there is little doubt that dietary versatility has been key to the success we’ve had.
Why must academics lose all grip on common sense? Let’s flip this question back around and simply ask: what particulars are absent (either completely, or in easily available, extreme doses) across all traditional diets? Hyperpalatable foods engineered precisely to have no brakes, perhaps? But seriously, it’s blatantly obvious to the most casual observer that our adaptability and ingenuity as a species has painted us into a corner because of our hubris. That is to say, we figured we could outsmart mother nature; have our cake and eat it too, as it were. And (of course) make a profit at the same time. That we, unlike any other living thing in our world, could engineer escape velocity from the gravitational pull of our required epigenetic input. That our surroundings didn’t matter. As if we — unlike any other living thing — were somehow special, unaffected by our epigenetic input. Or if the hit was too egregious, we could “science” our way around it. That approach has clearly trainwrecked our collective health.
Many paleoanthropologists today believe that increasing climate fluctuation through the Pleistocene sculpted our ancestors—whether their bodies, or their wit, or both—for the dietary flexibility that’s become a hallmark of humanity. The basic idea is that our ever-changing world winnowed out the pickier eaters among us. Nature has made us a versatile species, which is why we can find something to satiate us on nearly all of its myriad biospheric buffet tables. It’s also why we have been able to change the game, transition from forager to farmer, and really begin to consume our planet.
Which is all fine and well until we consider that we’ve creatively engineered an environment to satisfy our “hardwired” needs for laziness and gluttony. This is not a moral failing; it’s simply that we are blinded by this deep encoding and drive. And, like any deep encoding (and because of our “blindness” to it), we deny it.
This is the same psychological quirk that has us struggle against addictions of all sorts, and would have people smoke (for example) even in light of overwhelming evidence of its negative impact on health. We understand that these addictions are physical, yes — but we vastly underestimate the psychological aspect.
And all of us (myself included) vastly underestimate our ability to control our evolutionary “hardwiring” and our cultural conditioning and imprinting. We consider these subconscious machinations so much “woo”; that we’ve somehow risen above any attempt (if, in fact, it were ever true) that the subconscious is the true puppeteer of our lives. And yet, if you’ve ever dealt with the psychology of change at the rubber-meets-the-road level, you know, first hand, just how complicated human psychology can be. We are completely blind to those aspects of ourselves that yield the most control over our lives.
So just as there are limits to the amounts of environmental toxins we can safely endure, there is a limit to our dietary flexibility. We were not meant to be fat, diseased, and incapable of avoiding that which is clearly killing us. But just as a smoker squelches the volume on the cancer threat, so does the majority squelch the idea that food matters.
Whether we call it “Paleo”, or “the diet which has yet to be accurately named, defined and cataloged” is of no real importance. What is important is that we alter our epigenetic input, including what we eat, to more closely align with our evolutionary requirements for health. This is already taking place on a wide scale (nothing short of a revolution) among those who posses an epistemocratic nature and who take responsibility for their own health. Quite simply, those who don’t will have to, unfortunately, suffer the crippling consequences of degraded health.
Upward and onward.
Heal thyself, harden thyself, change the world –