A study of the evolution of our teeth over the last 7,500 years shows that humans today have less diverse oral bacteria than historic populations, which scientists believe have contributed to chronic oral diseases in post-industrial lifestyles.
The researchers, from the University of Adelaide's Australian Centre for Ancient DNA (ACAD), the University of Aberdeen (Dept of Archeology), Scotland, and the Wellcome Trust Sanger Institute, Cambridge, England, published their study in Nature Genetics.
The authors say that analyzing the DNA of calcified bacteria on the teeth of humans throughout modern and ancient history "has shed light on the health consequences of the evolving diet and behavior from the Stone Age to modern day".
The scientists explained that there were negative changes in oral bacteria as our diets altered when we moved from being hunter-gatherers to farmers. Further changes were observed when humans started manufacturing food during the Industrial Revolution.
Study leader Professor Alan Cooper, ACAD Director, said, "This is the first record of how our evolution over the last 7500 years has impacted the bacteria we carry with us, and the important health consequences."
The introduction of processed sugar may have completely changed the composition of oral bacteria in humans.
"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 scientists extracted DNA from calcified dental plaque (tartar) from 34 prehistoric human skeletons from northern Europe. They examined the changes in the nature of oral bacteria that were first present in prehistoric hunter-gatherers, through to the Bronze Age when farming became established, then to Medieval times and finally to the Industrial Revolution and later.
Dr Christina Adler, lead author, who was a PhD student at the University of Adelaide during the study, said "Genetic analysis of plaque can create a powerful new record of dietary impacts, health changes and oral pathogen genomic evolution, deep into the past." Dr. Adler now works at the University of Sydney.
The modern mouth exists in a permanent disease state
Professor Cooper said:
"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 in 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."
Professor Cooper has been working with Professor Keith Dobney from the University of Aberdeen on this for the last 17 years. Professor Dobney said "I had shown tartar deposits commonly found on ancient teeth were dense masses of solid calcified bacteria and food, but couldn't identify the species of bacteria. Ancient DNA was the obvious answer."
Scientists examined tartar deposits found on ancient teeth in their study. (Photo: Alan Cooper/University of Adelaide)
Prof. Dobney explained that this study provides a completely new window on how human populations lived and died in the past. If we know the real genetic history of diseases humans still suffer from today, scientists might better understand them, and even treat them more effectively. "Being able to track them through time has huge implications for understanding the origins and history of human health - making the archaeological record extremely relevant and important to modern-day medics and geneticists," Dobney added.
In an Abstract in Nature Genetics, the authors wrote that "modern oral microbiotic ecosystems are markedly less diverse than historic populations, which might be contributing to chronic oral (and other) disease in postindustrial lifestyles."
It was not until 2007 that the team could control background levels of bacterial contamination properly. This became possible when ACAD's super-clean labs and stringent decontamination and authentications protocols became available.
The scientists are now expanding their studies geographically and chronologically, and including other species, such as Neanderthals.
There is some evidence that beeswax was used 6,500 ago in dentistry, scientists from Abdus Salam International Centre for Theoretical Physics, Italy, explained in the open access journal PLoS ONE on 19th September, 2012.
Written by Christian Nordqvist
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Speculation: It's the Processed Foods
posted by dave on 27 Feb 2013 at 11:09 am
60 years ago, the "modern grocery store" did not exist as it is now. It was very different. We fed ourselves by growing and creating our own foods, bringing our excess to market, which was the local general store. We bartered for services with food. Food did not travel from South America or China. It was harvested locally.
Jessie hits it on the head.
Sugar was only natural, not refined. What is called food is actually poison, and should be shunned. (this is just about anything that isn't in the produce aisles.
Medical report and images on modern diet and why it rots our teeth
posted by qadar on 19 Feb 2013 at 7:58 pm
i need medical report and image pictures especially this field and other medical part every thing i need to understand some thing please give me more information about it that is my opinion and what i need it thanks
According to Weston A. Price's research back in the early 1900's, traditional diets included the consumption of a lot more bacteria as well. So, yes, we eat a lot of sugar and processed foods that feed "bad" bacteria but we also eat our foods very sterile i.e. we are no longer eating the "good" bacteria in things like raw dairy, fermented vegetables and grains, etc that used to be staples of our diets.
It's true A study of the evolution of our teeth over the last 7,500 years shows that humans today have least diverse oral bacteria than historic populations, which scientists believe have contributed to chronic oral diseases in post-industrial lifestyles. I am also working with gum disease treatment clinic in VA so I do a search on that many times.
posted by Jessie Barbera on 18 Feb 2013 at 2:00 pm
The study spans from 7,500 years ago and the big change was noticed 150 years ago, during the industrial revolution, when we started processing foods and sugar a lot. 150 years ago mouthwashes and toothpastes etc were not that widely used.
The difference is definitely linked to our change in diet, slanting more to carbohydrates and processed sugars and foods.
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