Most people think of charcoal as something you throw on the barbeque, but it has been used since Egyptian times for anything from purifying water to getting rid of bad smells. In Ancient Greece, Hippocrates treated his patients with charcoal and the Romans ground it up to clean their teeth.
Today, activated charcoal continues to be used in hospitals and water treatment plants. Its porous structure means it soaks up poisons and harmful chemicals. But in recent years, this ancient substance has been emerging as a hot new ingredient in the dental and beauty industry.