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A chewing stick that Namibians use to clean their teeth has been shown to
contain chemicals that kill the bacteria responsible for cavities and gum
disease. Researchers in the US and South Africa identified six antibacterial
compounds in muthala (Journal of Agricultural and Food
Chemistry, vol 48, p 909). 鈥淎ntimicrobial chemicals added to modern toothpaste
are equivalent to levels we get from the chewing stick,鈥� says Christine Wu of
the University of Illinois, Chicago.