The very foundation of the Paleo diet could be shaky, a new study has found.
The controversial diet, which promotes large amounts of vegetables and meats and no grains, assumes the human body has changed very little since prehistoric times, and thus eating like a hunter-gatherer must be good for us.
A team of US researchers recently put this idea to the test, and their findings published in Nature Communications suggest the guts of modern humans may changed substantially.
The team compared the gut bacteria of a group of hunter-gatherers and a group of farmers in the Amazon to a group of American academics eating mostly processed foods.
As you might expect, the gut bacteria of the hunter-gatherers and farmers was more diverse.
Alarmingly, an entire type of bacteria (Treponema) common to the remote communities was “absolutely absent” from the Americans, which has been confirmed by other studies.
“[I]t is absolutely absent, not detectable in industrialised human populations,” the study’s co-author Christina Warinner told Science Magazine.
Eating paleo does not seem to regrow these bacteria.
“So even if you could mimic a true paleo diet, you are still missing ancestral gut bacteria that were involved in food digestion in the paleo gut,” another of the study’s co-authors Cecil Lewis said.
The study does not prove whether Paleo is harmful or helpful, but does challenge the assumption we can eat and digest like our ancestors.