MEAT: THE ORIGINAL HUMAN DIET
[Excerpted from Primal Body, Primal Mind by Nora Gedgaudas]
The hunter- gatherer diet can be described via at least two different perspectives: ice age Paleolithic and post–ice age, or neo- Paleolithic. The diet of neo- Paleolithic peoples, including modern- day hunter- gatherers with some regional variation, essentially consisted of high- quality animal- source protein, both cooked and uncooked (including organ meats of wild game, all clean), that was hormone- , antibiotic- , and pesticide- free, naturally organic, and entirely range- fed with no genetic alteration. This diet included some eggs, when available, insects (sorry to say), and seafood. This diet was typically moderately high in fat, calorically, at a rate estimated to have been roughly ten times our modern intake (and fat was highly coveted). This included varieties of saturated, monounsaturated, and omega- 3 fats, and balanced quantities of omega- 6 fats, together with abundant fat- soluble nutrients.
Neo- Paleolithic, primitive human diets, as well as diets during more temperate periods amid the ice age, generally included a significant variety of vegetable matter, some fresh raw nuts and seeds, and some very limited quantities of tart, wild fruit, as was seasonally available. There was far more plant material in the diets of our more recent ancestors than our more ancient hominid ancestors, due to different factors. The current ice age (yes, “current”), known as the Pliocene- Quaternary glaciation, started about 2.58 million years ago, around the time the first hominids appeared, during the late Pliocene era, when the spread of ice sheets in the Northern Hemisphere began. Since then, the world has seen cycles of glaciation, with ice sheets advancing during extended time periods called glacials (glacial advance) and retreating during time periods called interglacials (glacial retreat).
The earth is currently in an interglacial period, and the last glacial period ended close to 11,500 years ago. In 1976, scientists at the Lamont- Doherty Earth Observatory spearheaded a project called Climate: Long- Range Investigation Mapping and Prediction (CLIMAP) to map the history of the oceans and climates. They exhaustively studied core samples and discovered that major cooling and glacial advances begin or end, almost like clockwork, every 11,500 years. Every one hundred thousand years or so, this transition to a major, especially brutal deep freeze occurs in a surprisingly abrupt manner, at times over no more than a few seasons. They refer to this regularly varying cycle of cooling periods as the Milankovitch cycle, also sometimes referred to as “the pacemaker of the ice ages.”
There can be no question that our physiology is profoundly influenced by this climatologic history. We have spent highly significant time periods during our ancestral history locked in the grip of mostly ice and snow, with only the briefest periods of warmer reprieve when edible plant life could have grown over a significant portion of the Northern Hemisphere. Periodic swings in climatic conditions, from relatively brief periods of reasonably temperate conditions to prolonged, harsh, ice age conditions, are more recently understood by climatologists to have been relatively rapid. Back in the late 1980s, a group of scientists known as the Greenland Ice Core Project (GRIP) drilled cores almost two miles deep into the ice, drilling deep enough to reach ice that had formed 250,000 years ago. By analyzing the data this provided, it was realized that each and every ice age during the last 250,000 years actually began quite abruptly, typically (ironically) following spikes in global temperature.
Each time this change occurred, the climate descended into full- blown glacial severity within less than twenty years, sometimes well within ten years! Only those people adapted in their physiology and cunning would have survived such sudden onsets of frigid, and unforgiving conditions (Calvin 2002). Even while the Northern Hemisphere was gripped in snow and ice during these periods, Africa was being ripped apart by droughts and wildfires, with catastrophic areas of flooding elsewhere. During any ice age, the entire planet endures a relentless range of such extremes. Studies of ancient human coprolites, or fossilized human feces, dating anywhere from three hundred thousand to as recent as fifty thousand years ago, have revealed essentially a complete lack of any plant material in the diets of the subjects studied (Bryant and Williams- Dean 1975).
In other words, it is likely we subsisted for a very significant portion of our evolution largely on the meat and fat of animals we hunted. Fat was the prime commodity for its concentrated nutrient and energy value. This has even been true of neo- Paleolithic hunter- gatherers and traditional societies, as clearly shown by the exhaustive scientific work of Weston A. Price first published in 1939 (Price 1989). As omnivores and opportunists, we would always have certainly procured whatever might have been available to us for food. Permafrosts and droughts, however, left many of us limited options for long stretches of time. Fat, too, is our most efficient, dense, and prolonged- burning fuel. It is essential for an important multitude of bodily processes, not the least of which is the functioning of the human brain.
Another important limitation stems from the fact that we as a species have only relatively recently developed a universally controlled use of fire. By most accounts, this did not occur before fifty thousand to one hundred thousand years ago. Although scattered evidence of fire exists from as far back as three hundred thousand to four hundred thousand years ago, it is unlikely that the sophisticated development of cooking practices occurred much before the use of fire became more universal and commonplace— sometime after Cro- Magnon man migrated into Europe. (The oldest- known pottery dates only as far back as 6800 BCE, incidentally.)
What makes the use of cooking especially significant is the toxicity of most plant species. Wild plants contain any number of toxic compounds that would have made their use as food in any significant quantity perilous. Cooking is the only means by which many of these “antinutrients” can be neutralized. Modern produce has been genetically modified to reduce the presence of harmful compounds to a significant extent. Most wild plants, on the other hand, require extremely careful selection and preparation. Most starchy roots, tubers, and legumes would have been prohibitively dangerous to consume without extensive cooking.
Furthermore, the energy expended in the procurement of the remaining types of plant foods easily exceeds their potential caloric value, to say little of their meager, inferior available protein content, which is so critical to our needs. Mass die- offs of megafauna following the last ice age ten thousand years ago and over- hunting by humans may have led to an increased dependence on plant foods and ultimately to the development of agriculture. Some people also hypothesize that it was an addiction to the exorphins (morphinelike compounds) in grains that sparked this widespread development.
Nonetheless, it is widely accepted that it was, in fact, our extended dependence on the meat and fat of animals (rich in eicosapentaenoic acid, or EPA; and docosahexaenoic acid, or DHA) through these frozen winters of unimaginable duration that allowed for the rapid enlargement and development of the human brain. Meat and especially fat would have been the most coveted and important commodities of all. We never would have survived as a species without them. Our increased dependence on hunting also likely helped facilitate and develop the very human qualities that we most intrinsically value— cunning, cooperation, altruism, sharing, advanced creativity, the power to foresee the future and to be able to call upon the past in terms of the future, the capacity to evaluate with complexity, and the ability to imagine solutions— qualities not particularly found in other primates (Ardrey 1976).
Also, interestingly, the dominant form of fatty acids in the human brain is omega- 3; in chimps and other primates, it is mostly omega- 6. This is a very significant distinction and one that is the likely result of these evolutionary, ice age–induced dietary changes. Many authors popularizing the notion of Paleolithic diets base their conclusive evidence on the diets of more- contemporary primitive peoples, forgetting that for most of our evolution, the world has been a very, very different place. Either way, it is evident from even the most recent analysis of primitive diets that animal- source foods and fat- soluble nutrients invariably play a critical, central role in such peoples’ extraordinary physical and mental health and freedom from disease, as characterized in primitive peoples and more traditional groups. It is also quite evident that diets consisting of any significant quantity of carbohydrates are a strictly modern phenomenon, one that our ice age human physiology has evolved little adaptation to— or defense against.
Carbohydrates, other than the largely indigestible variety found in fibrous vegetables and greens, have generally played a minimal role at best through most of human evolution. Fruit was consumed only seasonally by our neo- Paleolithic ancestors in most places, and wild fruit is extremely fibrous and smaller in size, with less total sugar content. Many potatoes and tubers would have required extensive cooking to neutralize extremely toxic alkaloids. Wild varieties that would have been available to us through most of our history as a species can be especially toxic. In other words, it isn’t likely we were eating baked potatoes with our woolly mammoth steaks— or much starch at all. In fact, of all the macronutrients (that is, protein, fats, and carbohydrates), the only ones for which there are no actual human dietary requirements are carbohydrates.
This is a critical and very fundamental point to remember: we don’t ever have to eat any sugar or starch of any kind at all in order to be optimally healthy. Our bodies can manufacture glucose, as needed, from a combination of protein and fat in the diet. As a matter of fact, glucose is really needed only in an ongoing way mainly for fueling our red blood cells. Most organs and tissues in the body, including the brain, actually prefer, if we let them, to use ketones, the energy- producing by- products from the metabolism of fats. This fact is very overlooked or misunderstood by the majority of medical and nutritional experts. There is abundant evidence that many modern disease processes, including those resulting in cardiovascular disease, elevated triglyceride levels, obesity, hypertension, diabetes, hypoglycemia, and cancer, to name a few, are the product not of excess natural fat in the diet, but of excess carbohydrates.
[Excerpted from Primal Body, Primal Mind by Nora Gedgaudas]
A recently published study of the skeletal remains of “The Red Lady of El Mirón” supports the consumption of a predominantly all-meat diet even by our Neolythic human ancestors. Her diet was comprised almost entirely of red meat, with some fish thrown in for good measure. Plant foods were almost non-existent. As reported in the New Scientist:
The paleo diet, for real…
Do you want to keep on-trend with the latest fashionable diet? Then look to the Red Lady of El Mirón, who ate the Paleo diet almost 19,000 years ago.
For her, it was no fad. The isotopes in her dental enamel, microscopic wear patterns on her teeth and the stuff embedded between them reveal that the meat of hoofed animals made up about 80 per cent of her diet. That means you might want to add red deer and ibex to your shopping list. Pick up plenty of salmon, too – fish seems to have made up most of the rest of her diet.
If that sounds a little dull, fear not. Meticulous dental analysis reveals she also ate some starchy plant material, most likely to have been seeds, plus mushrooms, although probably in small amounts (Journal of Archaeological Science). Whether fungi were eaten for nutrition or for some other purpose is unknown, says Lawrence Guy Straus of the University of New Mexico.