A new Cochrane review of the research confirms that suspicion. So far, there doesn’t seem to be enough good quality evidence to say much at all about xylitol’s ability to counter decay. Of the 10 studies the authors included, 7 were found to be “at high risk of bias.” Only one was considered at low risk.
Bias wasn’t the only problem, however. According to a press release on the findings,
In most cases, the studies used such different methods that the researchers could not combine the results to create a summary effect estimate. Based on information from 4,216 school children who took part in two Costa Rican studies, they found low quality evidence that levels of tooth decay were 13% lower in those who used a fluoride toothpaste containing xylitol for three years, compared to those who used a fluoride-only toothpaste. For other xylitol-containing products, such as xylitol syrup, lozenges and tablets, there was little or no evidence of any benefit.
So does this mean ditch the xylitol? Not necessarily. It does mean it’s something you probably don’t want to rely on to keep you caries-free.
Even researchers who found positive results have noted that xylitol “is not the silver bullet.”
Indeed, no single, isolated intervention probably is.
Image by Østergaard, via Wikimedia Commons