A team led by oral biologist Hyun (Michel) Koo, D.D.S., Ph.D., at the University of Rochester Medical Center has discovered that the same traits that make cranberry juice a powerful weapon against bladder infections also hold promise for protecting teeth against cavities. Koo found that cranberry juice acts like Teflon® for teeth, making it difficult for the bacteria that causes cavities to cling to tooth surfaces. Stickiness is everything for the microbe Streptococcus mutans, which creates most cavities by eating sugars and then excreting acids that cause dental decay. “Scientists believe that one of the main ways that cranberries prevent urinary tract infections is by inhibiting the adherence of pathogens on the surface of the bladder. Perhaps the same is true in the mouth, where bacteria use adhesion molecules to hold onto teeth,” Koo said. Koo’s team also found evidence that cranberry juice disrupts the formation of the building block of plaque, known as a glucan.
Like a mason using cement to build a wall brick by brick, bacteria use enzymes known as glucosyltransferases to build dental plaque piece by piece, quickly forming a gunky fortress that covers the tooth and gives bacteria a safe haven to munch on sugar, thrive, and churn out acid. Koo’s team found that cranberry juice prevents bacteria from forming plaque by inhibiting those enzymes and by stopping additional bacteria from glomming on to the ever-growing goo.
“Something in the cranberry juice disarms the pathogens that cause tooth decay,” Koo said.
But don’t even think about running to the juice aisle in the grocery store to prevent tooth decay, Koo said. The sugar that is usually added to cranberry juice can cause cavities, and the natural acidity of the substance may contribute directly to tooth decay.