A team of researchers from all around the world has made the discovery that studying the plaque found on the ancient remains of our ancestors can provide hitherto undreamed of insights into the make-up of the diet which these people existed on. The plaque in question is that which was allowed to calcify and harden until it turned into calculus, which is hard enough to survive on the remains until the present day. By studying this substance, scientists were able to determine that the ancestors in question had a much greater understanding of edible plants, in a per-agricultural era, than had previously been realised. The Researchers The research in question was led by teams of scientists from Universitat Autònoma de Barcelona and the University of York, and took place at Al Khiday, a site dating from pre – historic times which is located in central Sudan, on the White Nile. In simple terms, the researchers took the calcified dental calculus which was present on the remaining teeth and extracted both chemical compounds and micro-fossils. By examining these, it was possible to draw conclusions about the nature of the diet that had been eaten and in particular the fact that the Purple Nut Sedge – now looked upon as a weed – was a staple part of that diet. This fact in itself indicates that these ancient people had an understanding of the medicinal and nutritional qualities of plant life. Outcomes The conclusions drawn and outcomes reached by the various researchers were far ranging. One of them was the complete switch in the way in which Purple Nut Sedge is viewed. Today, it is regarded as a hugely problematic and expensive weed, proving to be both difficult and time consuming when needing to be removed from agricultural areas in the tropics and sub-tropics. Back then, however, it was clearly highly valued both as a foodstuff and perhaps as a medicine. More recently (relatively speaking) it was utilised by the ancient Egyptians as a medicine and to make perfume. Other conclusions drawn by the researchers included the revelation that the ancient people also ate several other plants, that they cooked their food, and that they sometimes chewed on plant fibres to create raw materials for construction and so on. Cavity prevention The site itself is made up of 5 separate areas, all lying approximately 25 kilometres south of Omdurman, Sudan’s’ largest city. The fact that one of these areas was used as a burial ground across thousands of years meant that it offered an invaluable insight into the ways in which the diet eaten had changed over time. One of the factors noticed in the remains was the good condition in which the teeth themselves survived, exhibiting relatively low numbers of cavities. The researchers felt that this might be due to the fact that Purple Nut Sedge acts as an antidote to the bacteria Streptococcus mutans, which is known to cause tooth decay. Another conclusion drawn was that Purple Nut Sedge remained a vital part of the diet for all of these people, despite the wide time range being covered and the fact that the latter stages post-date the development of formalised agricultural methods. The findings, and the increased study of chemical compounds and micro fossils, also helped to counter the prevailing view that the diet of such ancient people consisted mainly of meat and protein. The overall conclusion of the study is that our ancient ancestors had a much more sophisticated and wide ranging diet than has previously been thought possible, and that there knowledge of the benefits of plant life was far in advance of what had previously been assumed. It also became clear just how much can be gleaned about the lives of those who came before us by studying the teeth and, in particular, the calculus that remained. Next time you’re cleaning your teeth or opting to take dental treatments in London take a few seconds to think about the fact that the oral health decisions you take today might well be setting down vital clues for the archaeologists of tomorrow.