Ancient tooth decay DNA reveals effects of changing diets

A man from Europe's first farming culture, around 7,000 years ago showing dental calculus and growth lines on one tooth characteristic of nutritional stress during youth. Germany. Study leader Professor Alan Cooper, director of ACAD said: “This is the first record of how our evolution over the last 7,500 years has impacted the bacteria we carry with us and their important health consequences. “Oral bacteria in modern man are markedly less diverse than historic populations and this is thought to contribute to chronic oral and other disease in post-industrial lifestyles.” The development of farming around 10,000 years ago caused a major shift in human diet, resulting in a significant impact on our health. The same was true of the much more recent move to eating highly processed flour and sugar, both of which have contributed directly to health problems we see today such as tooth decay, diabetes, and heart disease. Professor Cooper added: “The composition of oral bacteria changed markedly with the introduction of farming, and again around 150 years ago. With the introduction of processed sugar and flour during the Industrial Revolution, we can see a dramatically decreased diversity in our oral bacteria, allowing domination by caries-causing strains. The modern mouth basically exists in a permanent disease state.” Ironically, the introduction of sugar and carbohydrates contributed to the increase in dental plaque that now holds the vital information the scientists are studying. Professor Dobney added: “Until now we’ve had to rely mainly on indirect evidence or historical documents to tell us what people ate and what kind of illnesses they suffered from in the past. But now we can directly extract genetic information on diet and health from the tartar on teeth — which is very abundant and well-preserved in the archaeological record — and we have a totally new source of unique information stretching back thousands of years.” Dr. Julian Parkhill, co-author from the Wellcome Trust Sanger Institute said: "We have shown that genetic sequencing is not restricted to modern samples. Sequencing the oral microbiota of different populations, over the ages, from across the world will tell us how different diets have affected human health, opening a whole new area of research. Professor Dobney and Professor Cooper have been working on the project for the past 17 years but only since 2007 has it been possible to carry out the research as a result of ACAD’s ultra-clean laboratories and strict decontamination and authentication protocols. The research team is now expanding studies through time, and around the world, including other species such as Neanderthals.