Gum-chewing might be occasionally annoying and result in messy sidewalks, but there's one thing it does extremely well other than blow bubbles: kill cavity-causing microbes in your mouth.
A new study in PLoS One has found that chewing gum is actually a sticky apocalypse for harmful oral bacteria. Just one piece of gum can obliterate up to 100 million germs, or about 10% of the total microbial load in human saliva.
The study: A team of researchers at the University Medical Center at the University of Groningen in the Netherlands gathered five graduate students to perform the arduous task of chewing the gum. The volunteers were asked to chew two separate varieties of chewing gum for time periods ranging from 10 seconds to 30 minutes. The gum was spat out, and the microbial contents within were analyzed using a variety of methods, including dissolving it in chemicals.They found that the longer the students chewed, the more bacteria that was absorbed, but the effects plateaued after 30 seconds.
The research team concluded that "bacteria are killed during their entrapment in the gum by sweeteners like xylitol, food preservatives or flavoring agents like spearmint and peppermint, which are reported to have antimicrobial properties."
But this isn't a get-out-of-brushing-free card: Gum makes a pretty decent showing compared to other methods, and the team thinks that the effects are roughly the equivalent of using a new toothbrush with no toothpaste or flossing. However, each of these tasks need to performed separately as they reach different areas of the mouth, meaning it's unlikely chewing gum could supplant traditional brushing.
Additionally, this only really applies for sugar-free gum. While regular gum might absorb some of the bacteria in the mouth, it also leaves behind lots of sugar for the remaining microbial population to feast upon. (Another dental hygiene trick that could backfire is using microbead-laden toothpastes, which could potentially lodge in your gums and cause gingivitis.)
In addition to showing that chewing gum can be part of a healthy smile, the researchers believe that their methods could one day lead to much more effective gums that scrub away even more bacteria. Just don't take it all at once, please.