Is the Paleo Diet a Myth? Cavemen Likely Ate a Plant-Based Diet

The popular paleo diet guides people to adopt the supposed eating habits of our ancient ancestors, focusing heavily on lean meats, as well as fish, eggs, vegetables, fruit, nuts and seeds. But new research appears to bust the myth that cavemen ate a very meat-forward diet.

A new study, published by Nature, found that hunter-gatherers actually consumed more vegetables and suggested they favored what has become known as a plant-based diet.

Researchers conducted an advanced isotopic analysis of bones and teeth — from the remains of a Paleolithic group called the Iberomaurusians — found in a Taforalt cave in Morocco that was inhabited roughly 15,000 years ago.

They discovered that the Stone Age diet "unequivocally" demonstrated "a substantial plant-based component."

"This distinct dietary pattern challenges the prevailing notion of high reliance on animal proteins among pre-agricultural human groups," the researchers wrote.

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According to the study, the presence at the site of plant processing tools such as grinding stones, as well as a higher incidence of dental cavities and periodontal diseases, supports the predominance of plant foods in the Iberomaurusians' diet.

Evidence suggests that the group ate a lot of “fermentable starchy plants,” in particular, such as acorns, pulses or wild cereals.

Analysis of the nitrogen levels contained in the collagen and tooth enamel indicated that up to 80% of the food eaten by the inhabitants of the Taforalt cave was plants.

The researchers noted, however, that some animal protein was consumed, as cut marks were observed on the faunal assemblage, a group of animal fossils found together in a stratum, providing evidence of the butchery and processing of animals at that time.

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Researchers also noted the potential early weaning of infants at Taforalt using starchy plant foods, underscoring "the notion of a plant-based food focus for the population, potentially extending to the primary source of nutrition for infants."

“This contrasts with hunter-gatherer societies where extended breastfeeding periods are the norm due to the limited availability of weaning foods,” they wrote.

The researchers also suggested that the increased reliance on plant foods among the Iberomaurusians was likely driven by several different factors, including the availability of a wider range of edible plants and a depletion of large game species.