The Truth About the Caveman Diet
Faulty premises behind the paleo diet
Posted Nov 22, 2013
Many readers will have heard of the ‘caveman diet,’ also known as the ‘paleo diet,’ an eating regime based on the premise that we should eat what our ancestors ate over the course of human evolution. More specifically, it suggests that we eat meat, fruit, and nuts and maybe some fish—foods that hunters and gatherers eat—and avoid foods like grains, beans, and potatoes that are the basis of agricultural diets. After all, what could be better for us than to eat what we evolved to eat? So, chuck your food pyramid and dig into that steak! You will be fulfilling your natural evolutionary destiny. Or maybe not.
Most paleoanthropologists just sigh when they hear this nonsense. It is based on ignorance of the paleoanthropological record, and also a serious fallacy in reasoning known as the Naturalistic Fallacy—the assumption that anything natural must be good. We’ll leave the fallacy to the philosophers, and focus on the ignorance. We should make clear here that we are not crazy enough to advocate for one diet over another; the only topic that would get us more irate emails would be religion. But we do want to point out that the premises of the caveman diet are wrong.
First, there was not one Palaeolithic diet; there were many. Diets varied according to local availability, according to technical know-how, and according to simple taste. In tropical habitats hunters and gatherers tend to rely heavily on gathered plants, including often grains and tubers. In higher latitudes, where primate-friendly plants are fewer, hunters and gatherers rely more on animal protein. This is true among modern hunters and gatherers, and was true for most of human evolution. The advocates for a caveman diet do have one thing sort of correct: meat has been a significant component of hominin diets for probably two million years. Indeed, we may have meat to thank for our large brains (which we addressed in a previous blog and more on this in another post). But the percentage of meat in the diet varied dramatically over the course of human evolution. Humans have always been pretty eclectic in their dietary choices, as they had to be in order to expand into so many different habitats.
The second error in premise is perhaps even more significant. The caveman diet is a great diet if you want to live to be 30 or 35 years old. That was the adult life expectancy until very, very recently (indeed, it wasn’t until well after the advent of agriculture that life expectancies began to rise—in agricultural communities!). We know this from skeletal evidence. Individuals older than 40 at death are very rare in the Palaeolithic record. At the 300,000 year old Spanish site of Sima de los Huesos, archaeologists found the remains of 32 individuals who had been dropped down a shaft in a cave. They appear to have died natural deaths, and none of them was over thirty years of age. It wasn’t that the caveman diet killed these people. It is just that almost no one lived long enough to develop the medical conditions we associate with long-term consumption of large quantities of animal protein and fat. Thus, just because cavemen did it does not mean it is good for you.
Of course, the true cavemen were Neandertals, and you probably would NOT want to take up a Neandertal way of life, or even a Neandertal diet. We actually know a lot about Neandertal diets from the remains of their meals, sites where they slaughtered animals, and chemical signatures in their bones. One of the most famous Neandertal’s skeletons was found near La Chapelle, France. Because of the poor condition of his teeth, many missing (although there was evidence that his gums had healed in some places), with a scraggily tooth in front, and evidence of arthritis in his bones and joints, he was called the Old Man of La Chapelle. He lived between about 40,000 to 60,00 years ago. Current thinking is that The Old Man of La Chapelle was about 30 to 35 years old at the time of his death!
Neandertals have also been described as ‘top predators,’ which means that they appear to have preferentially targeted the largest ‘packages of meat’ on their local landscape. They did eat other things, including plants, but more than any other prehistoric group we know of they were heavily dependent on meat. And they appear not have had conservation in mind. Perhaps the most spectacular example of Neandertal carnivory comes from the site of La Cotte de St. Brelade.
La Cotte is a rocky headland above a beach on the Isle of Jersey. 160,000 years ago at the beginning of the next-to-last major glacial period, Jersey was not an island, but a peninsula. Water locked up in glacial ice had not returned to the oceans, and sea level had dropped. It was also colder. On two separate occasions Neandertals used the cliff at La Cotte to aid their hunt. In the most impressive episode they killed and butchered 11 mammoth and 3 rhinoceros (yes, there were rhinoceros in ice-age Europe). Most archaeologists think that Neandertal hunters somehow stampeded a herd so that the leaders were pushed over the cliff by followers. Other archaeologists think that Neandertals may simply have maneuvered the giant beasts into a tight spot at the base of the cliff. However they did it, it must have been a gruesome spectacle. Two remarkable facts stand out. First, Neandertals used hand-held thrusting spears. Second, they managed to acquire a HUGE amount of meat.
The University of Colorado, Colorado Springs, Center for Cognitive Archaeology offers a range of online courses and also graduate and undergraduate certificates in cognitive archaeology. Information available at http://www.uccs.edu/~cca/.