9,500-year-old chewing gum reveals ancient humans suffered from ‘notable’ diseases

Researchers recently spent some time chewing over prehistoric pieces of gum found in Sweden.

Their analysis revealed the diverse diet and “notable” dental diseases of early humans in Scandinavia, according to a study published Jan. 18 in the journal Scientific Reports.

The study was conducted on three pieces of chewed pitch — dating back around 9,500 years — found on the island of Orust, located on the western coast of Sweden.

The ancient globs were found three decades ago alongside stone tools, according to a news release from Stockholm University. Through DNA analysis, they were linked to three teenage individuals, who were likely camping, hunting and fishing in the area.

The DNA found on the pieces — the oldest known human genetic material in Scandinavia — indicate the group of hunter-gatherers had poor oral hygiene.

“We reconstructed several ancient bacterial genomes and found notable amounts of oral pathogens,” researchers said.

The bacteria Streptococcus, which can lead to dental cavities, was located on the chewed gum. An abundance of other bacteria, including Actinomyces and Treponema, were also found.

These results comport with what is known about the ancient populations in Sweden, researchers said.

“The Mesolithic population density was low, with limited possibilities for pandemic-causing microbes to spread between humans, but not restricting the presence of bacteria from other sources than humans, like for example those causing systemic diseases including infective endocarditis,” researchers said. “The wider use of the teeth, as tools, likely increased the risk for collecting periodontitis causing oral microbes.”

In addition, traces of various plants and animals were observed on the chewed gum, indicating they had recently been consumed.

DNA sequences from red fox, trout, red deer, apple and hazelnut were all observed, reflecting a diet composed of both terrestrial and marine life, researchers said.

The results provide an “amazing” window into the lives of “a small group of hunter-gatherers on the Scandinavian west coast,” Anders Götherström, one of the study authors, said in the release.

This story was originally published January 22, 2024 at 3:07 PM with the headline "9,500-year-old chewing gum reveals ancient humans suffered from ‘notable’ diseases."