teeth Luckily, prehistoric people didn't brush their teeth. Otis Historical Archives Nat'l Museum of Health & Medicine / Wikimedia Commons

New archaeological research may have revealed that the original 'paleo diet' contained wheat and barley, and was not just restricted to meat and vegetables as the current diet typically is.

Scientists from Cambridge, Cardiff, UCL and York Universities studied the remains of nine people who lived around 9,000 years ago in the late Mesolithic (6600 - 6450 BC) and the Mesolithic-Neolithic phases (6200 - 5900 BC) and found plant matter fossilised in their teeth.

Thanks to poor dental hygiene, micro-fossils were trapped in ancient plaque on their teeth. The researchers say these plaques contain plants — cereals, in fact — that weren't thought to be part of people's diets for another four centuries. 

"There has been a long-standing view that for the most of the Palaeolithic times, but also in the Mesolithic, animal protein coming from meat and fish was the main staple food with a very limited role of plant foods," lead researcher Dusan Borić told Business Insider. 

prehistoric bones Mysteries were revealed from human teeth remains. Dr Dušan Borić / Cardiff

People in the Mesolithic period are generally believed to have been hunter-gatherers and lived in vast woodlands. The Neolithic, or New Stone Age, came afterwards, and it's then that people were believed to have first planted cereal crops and developed agriculture.

The discovery of domestic cereals in Mesolithic people's diets means that social networks between local foragers and the first Neolithic communities probably extended further than archaeologists originally thought, due to how deep into the Balkan hinterland they were found.

"At the time of the discovery we had the sense that these groups of complex hunter-gatherers were in contact with other more distant locations," Borić said. "We found beads made of marine gastropods that come from coastal areas in Greece and the Adriatic, hundreds of kilometres away from the region for instance."

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