Anyone who survived to adulthood in the Viking Age probably had terrible teeth. Researchers examining Viking skeletons have uncovered signs of infected gums and worn molars, and new findings show that the Vikings had another problem to worry about: cavities.

To understand the Vikings’ dental health, Carolina Bertilsson at the University of Gothenburg in Sweden and her colleagues examined the jaws and teeth of 18 Viking men and women whose remains were unearthed from a 10th-century graveyard on the Swedish island of Gotland — and found that only four individuals had no cavities. The prevalence of tooth decay might be linked to an ancient diet that included fruits, berries, honey and mead, a honey-based alcoholic drink. The researchers also found evidence of jaw-bone infections and tooth loss.

The researchers note, however, that the Vikings, who lived well before modern dentistry, had fewer cavities than today’s humans.