'World's costliest weed' may prevent cavities
Wednesday, July 16, 2014, 4:25 PM - Purple nutsedge, or Cyperus rotundus is considered one of the most abundant weeds on Earth. It can be found in 90 countries -- including Canada and the U.S. -- and it is hardy, difficult to control and has the ability to devastate crops and ornamental plants.
Today, farmers pay big bucks to have the weed removed from their land, but centuries ago it may have played a critical role in the oral health of ancient African populations.
Scientists have analyzed calcified tooth plaque from prehistoric skeletons and discovered that people ate the weed for thousands of years.
"This plant is a good source of carbohydrates and has many useful medicinal and aromatic qualities, though today it is considered to be the world's most costly weed," The study's authors write.
"Its ability to inhibit Streptococcus mutans [a bacteria linked to tooth decay] may have contributed to the unexpectedly low level of caries [i.e., tooth decay] found in the agricultural population."
The team used a variety of techniques to examine the teeth of 20 skeletons that inhabited modern-day Central Sudan.
Researchers told the Toronto Star they were "surprised" to learn they ingested purple nutsedge.
"The development of dental caries is strongly associated with diet [and] ... the presence of caries also increases with age," the study says.
" ... As the type of food ingested can have a direct effect on the health of teeth, we suggest that chewing C. rotundus tubers may have contributed to the unexpectedly low prevalence of dental caries in the Meroitic samples at Al Khiday and possibly also Gabati [Sudan]."
The complete paper can be read on PLOS One.