Groundbreaking research from Trinity College Dublin discovers evidence of tooth decay-causing bacteria, including Streptococcus mutans, in 4,000-year-old human molars from County Limerick, Ireland, providing new insights into the diets and lifestyle of ancient populations.
Researchers have discovered evidence of tooth decay-causing bacteria, including a significant presence of Streptococcus mutans, in 4,000-year-old human molars extracted from a limestone cave in County Limerick, Ireland. This groundbreaking study traces back the history of oral health issues such as cavities and gum disease to the Bronze Age, offering insights into the diets and lifestyles of ancient populations.
Published in the journal Molecular Biology and Evolution, the investigation was led by Assistant Professor Lara Cassidy from Trinity College Dublin. The study highlights the exceptional preservation of bacteria’s DNA in the cave’s cool, dry, and alkaline conditions, allowing for a detailed analysis of ancient oral microbiomes. The findings underscore the prevalence of oral health risks, such as cavities, likely influenced by the individual’s diet.
The research reveals substantial changes in oral bacterial composition over time, partly attributed to the increased consumption of sugars in modern diets. This adaptation of S. mutans and other bacteria to metabolize sugars illustrates the evolving challenge of tooth decay across millennia. It also points to the bacteria’s genetic adaptability, crucial for their survival and proliferation.
The study not only charts the evolution of human diets but also maps the genetic diversity and evolution of oral bacteria, such as those causing gum disease. By comparing ancient DNA with contemporary samples, researchers observed significant shifts in oral microenvironments, reflecting broader changes in human health and dietary practices over thousands of years.
This research provides valuable context for understanding the historical impact of diet on oral health and the genetic evolution of oral bacteria. It also offers potential directions for future studies in dental health practices, dietary patterns, and their effects on human wellbeing through time.
