Point to the Paleos: Settling Down on the Farm Made Our Bones Weak
Science has not been kind to the Paleo diet. Anthropologists have found that the food eaten by our Paleolithic ancestors included much more variety than present-day adherents of the high-protein, high-fat regimen would have you believe. On the health side of things, one recent study found that eating excessive amounts of protein is linked with an increase in the amount of a hormone that spurs the growth of cancer cells.
But now you can chalk one up to Team Paleo: Giving up our hunter-gather lifestyle and settling down on the farm made humans develop weaker bones. That’s the gist of a new anthropology study published in the Proceedings of the National Academy of Sciences that compared the bones of farmers from nearly 1,000 years ago and the even older remains of hunter-gathers who lived in the same area. Unlike the dense bones of the more ancient humans, the farmers had a lightweight frame with the same “spongy” bones humans have today.
While Paleo fanatics likely would not be surprised to learn that humans devolved to a certain extent around the time we went from foraging for crops to harvesting them, the news did catch anthropologists off guard. The change in bone structure occurred far more recently than the researchers had imagined. However, it had less to do with diet than lifestyle, according to the authors of the study, who had guessed the shift occurred way back when Homo sapiens first left Africa. Our closest ape relatives have the same kind heavyweight bones.
The authors say the lighter bones likely developed due to “lack of mobility and more sedentary populations,” as Timothy Ryan, an associate professor of anthropology at Penn State and a coauthor of the study, told NPR. “Definitely physical activity and mobility is a critical component in building strong bones,” he added.
So despite all of the calcium those farmers were likely able to access thanks to their domesticated livestock, it couldn’t make up for the lost exercise. Milk can only do a body so much good.