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Ancient Humans and Dental Health

Throughout evolution there was a sort of trade dental health off - or so it's been accepted. As hominids started consuming more soft starches (like grains, especially cooked), we accepted the detrimental effects of cavities over tooth wear/enamel erosion. (for a great read on the evolution of dentition, check out John Hawk's blog)

Before domesticated food and modern technologies, the teeth were subject to a lot more stresses that could wear away the enamel. When you start eating starchy crops, much softer after heat treatment and processing, this issue goes away - but another arises. Starchy crops are easily fermented by bacteria and also stick to teeth - the perfect formula for dental caries (cavities).

It's been generally shown across hominid fossils from the Paleolithic and Mesolithic that dental caries were a rarity - there is one famous Pleistocene skull found in Zambia that was replete with cavities. Even Neanderthal samples don't show much evidence of regular dental caries, though samples  with them exist (1,3).

However, new evidence suggests (2) that a high incidence of dental caries aren't just a product of the Agricultural revolution. The doubt comes from new samples of Pleistocene hunter gatherers in Northern Africa who lived about 14-15k years ago (before the advent of agriculture). These hunter-gatherers were eating wild foods, like acorn and pine nuts.

It's important to realize that the relative incidence of dental caries, and not their occurrence, is what's most groundbreaking about this study. It seems to me that those who follow ancestral diets and claim  cavities are a product of the agricultural revolution don't frequent the anthropology journals, which contain multiple examples of dental caries before Ag (4, 5, 6).

I'm in no way saying that you shouldn't still eschew added sugars and processed starches in your diet- but avoiding grains and thinking you're impervious to cavities is a false sense of assurance. Floss, brush your teeth, and eat a healthy diet, which can include starches. And take a note from your Neanderthal cousins and use toothpicks! (7)

1. http://www.uic.edu/classes/osci/osci590/11_1Epidemiology.htm
2. http://www.pnas.org/content/early/2014/01/03/1318176111
3. Grauer, A Companion to Pale
4. http://www.sciencedirect.com/science/article/pii/S004724848571055X
5. http://www.sciencedirect.com/science/article/pii/S0305440301906892
6. http://www.sciencedirect.com/science/article/pii/S0305440399905125
7. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0076852

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