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Ancient Skeletons Reveal the Cost of a Sweet Tooth

Sweet tooth

People today have far higher frequencies of decay-associated bacteria than during the agricultural or hunter-gatherer periods.

By Christina Adler

A genetic study of ancient oral bacteria in the calcified dental plaque of human skeletons shows that our ancestors had healthier mouths than us.

Christina Adler is an Associate Lecturer in the Faculty of Dentistry at the University of Sydney.

The full text of this article can be purchased from Informit.

Oral diseases such as dental decay and gum disease are extremely common in most countries around the world. For example, 60–90% of school-aged children in developed countries have cavities.

While dental diseases are now commonplace worldwide, the frequencies of dental decay and gum disease were rare in the not so distant past.

We can estimate the frequency of oral diseases though human history by looking at skeletal remains. By studying teeth and bones, we can look for the presence of tooth decay in the form of cavities and gum disease that is evident from pitting in the jaw bones around the teeth.

Skeletal remains from individuals that lived a hunter-gatherer lifestyle have shown that these populations had very good oral health, with low frequencies of dental disease. However, the presence of dental decay and gum disease in the skeletal record started to become more frequent approximately 10,000 years ago, and again even more prevalent around 150 years ago.

The increased frequency of oral diseases among human populations over the past 10,000 years is thought to be associated with two major changes to our diet. The first big change to diet during human evolution was caused by the development of agriculture, which involved the farming of grains such as wheat and barley. The farming and consumption of these grains meant that humans switched...

The full text of this article can be purchased from Informit.