Today's Paleo acolytes avoid grains, cereals, legumes, and other carbohydrates, favoring meats, nuts, and vegetables instead. The whole idea is that this is how our ancestors ate, and the diet we evolved for, too.
And yet, according to the new study, published in the Proceedings of the National Academy of Sciences, some hunter-gatherers from what is now Italy actually worked hard to eat carbs. They developed tools and multi-step heating technologies to process different grains, particularly oats and acorns.
To figure this out, the researchers, led by Marta Mariotti Lippi from the University of Florence, analyzed the residue on ancient grinding tools, discovered in the Apulia region of southern Italy. The evidence suggests that, 32,000 years ago, inhabitants of the southeastern part of Italy's boot were drying out plants, treating them with heat to accelerate their drying, and then grinding them.
The Southern Italians weren't alone in their carb-loving ways, Lippi told Vox. "In Central Italy they ate starch from cattail, in the Middle East, starch from wild wheat. In Russia and Moravia, they were eating starch, but we do not know which plants they processed."
This Paleolithic diet is very different from the one imagined by today's would-be cavemen.
This isn't the first study to debunk the Paleo diet
This new study builds on existing evidence that people in the Paleolithic era relied on grains, starch, and other carbohydrates to get by.
According to a recent Carl Zimmer piece in the New York Times, our evolution may have actually depended on carbs: "Scientists propose, by incorporating cooked starches into their diet, our ancestors were able to fuel the evolution of our oversize brains."
What's more, we didn't evolve to eat meat — a staple of Paleo dieters now. In a popular TED talk, anthropologist Christina Warinner explains that humans actually have "no known anatomical, physiological, or genetic adaptations to meat consumption." In fact, humans actually have many adaptations to plant eating.
In National Geographic, Ann Gibbons explains that while hunter-gatherers did eat meat, they also relied on "fallback foods" when meat was scarce — namely things like nuts, tubers, plantains, and water chestnuts:
"There’s been a consistent story about hunting defining us and that meat made us human," says Amanda Henry, a paleobiologist at the Max Planck Institute for Evolutionary Anthropology in Leipzig. "Frankly, I think that misses half of the story. They want meat, sure. But what they actually live on is plant foods."
This brings us to another important point: The Paleolithic diet isn't one single way of eating.
Much like the way people around the world eat today, Harvard paleoanthropologist and author of The Story of the Human Body Daniel Lieberman explained, "There are millions of Paleo diets. People in East Africa ate different foods than people in West Africa versus the Middle East, and South America, and North America."