The True Human Diet
The True Human Diet
Many have been debating the natural human diet for a huge number of years, often framed as a question of the morality of eating other animals. The lion has no choice, but we do. Consider the ancient Greek philosopher Pythagoras, for example: Oh, how wrong it’s for flesh to be made from flesh! The argument has not changed a lot 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, why He made them out of meat? Have a look at Genesis 9:3 – Every moving thing that liveth shall be meat for you.
While humans do not have the teeth or perhaps claws of a mammal evolved to kill and eat other animals, which does not mean we are not meant to eat meat, however. Our early Homo ancestors invented weapons and cutting tools in lieu of sharp carnivorelike teeth. There’s no explanation other than meat eating for the fossil animal bones riddled with stone tool cut marks at fossil sites. Additionally, it explains our simple guts, which look little like those evolved to process large quantities of fibrous plant foods.
But gluten is not unnatural either. Regardless of the pervasive call to cut carbs, there’s a lot of proof 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 barley and wheat 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 other grains and barley as well as the telltale damage that will come from cooking. There’s nothing new about cereal consumption.
This leads us to the so called Paleolithic Diet. As a paleoanthropologist I am often asked for the thoughts of mine about it. I am not actually a fan – I love French fries and pizza and ice cream too much. Nevertheless, diet gurus have built a strong case for discordance between what we eat now and what our ancestors evolved to eat. The concept is actually which our diets have changed way too quickly for our genes to keep up, and the result is actually said to be metabolic syndrome, a group of conditions that include elevated blood pressure, high blood sugar level, abnormal cholesterol amounts and obesity. It is a strong argument. Think of what could happen in case you put diesel in an automobile built for regular gasoline. The incorrect fuel is able to wreak havoc on the system, whether you are filling an automobile or perhaps stuffing the face of yours.
It makes sense, and it is no surprise that Paleolithic diets remain very popular. There are lots of variants on the common theme, but foods high in protein and omega 3 fatty acids show up once again and again. Grass-fed cow meat and fish are actually good, and carbohydrates should come from nonstarchy fresh fruits and veggies. On the other hand, potatoes, dairy, legumes, cereal grains, and highly refined and processed foods are actually out. The concept is usually to eat like our Stone Age ancestors – you know, spinach salads with avocado, diced turkey, walnuts, as well as the like.
I’m not a dietician and can’t 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 actually a myth. Food choice is just as much about what’s available to be eaten as it’s 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 readily available to our ancestors varied over deep time as the world changed around them from wet and warm to cool and dry and back again. Those changes are what drove the evolution of ours.
Even in case we could reconstruct the precise nutrient composition of foods eaten by a particular hominin species in the past (and we can’t), the info will be meaningless for planning a menu based on the ancestral diet of ours. Because our world was ever changing, too, so, was the diet of the ancestors of ours. Focusing on a single point in the evolution of ours will be futile. We are a work in progress. Hominins were spread over space, also, and those living in the forest by the river surely had a different diet from the cousins of theirs on the lakeshore or even the open savanna.
What was the ancestral human diet? The question itself makes no sense. Imagine several of the latest hunter gatherers who have inspired Paleolithic diet enthusiasts. The Tikiamiut of the north Alaskan coast lived almost completely on the protein and fat of fish and marine mammals, whereas the Gwi San in Botswana’s Central Kalahari took something like seventy % of the calories of theirs from carbohydrate rich, starchy roots and sugary melons. Traditional human foragers managed to make a living from the larger community of life that surrounded them in a remarkable variety of habitats, from near polar latitudes to the tropics. Not many other mammalian species are able to make the claim, and there’s very little doubt that dietary versatility has been crucial to the success we have had.
Many paleoanthropologists today think which increasing climate fluctuation through the Pleistocene sculpted the ancestors of ours – whether the bodies of theirs or perhaps the wit of theirs, or perhaps both – for the dietary flexibility which has become a hallmark of humanity. The fundamental concept is actually that our ever changing world winnowed out the pickier eaters among us. Nature makes us a versatile species, which is the reason we are able to find something to satiate us on nearly all its myriad biospheric buffet tables. It is also why we’ve been in the position to replace the game, transition from forager to farmer, and truly begin to consume the environment of ours.