Xylitol
A sweetener the bacteria cannot digest. The evidence is real, and it is weaker than the packaging suggests.
How to use it
As gum or a lozenge after eating, or as xylitol in your toothpaste. Not as a sugar substitute in your coffee: that is not what it was tested for and not where the point is.
The best version
Gum with xylitol as the first ingredient and no other sweeteners alongside it. Or a fluoride toothpaste with xylitol in it, because that combination is what the best evidence is about.
How to prepare it
After eating, chew for a few minutes. The chewing itself does something too: it makes saliva, and saliva is your own rinse.
What it does
The clearest result in the Cochrane review is about toothpaste. A fluoride paste with 10 percent xylitol gave 13 percent less decay over two and a half to three years than the same paste without it, across 4216 children.
Watch out
Cochrane calls that evidence low quality itself, and it comes from two studies by the same authors in the same population. Of the 10 included studies with 5903 participants between them, one was at low risk of bias and seven were at high risk.
Riley P, et al. Cochrane Database of Systematic Reviews, 2015.
For lozenges, sucking tablets and wipes the evidence was too weak to say anything, and in adults there is only one study. The adverse effects reported were cramps, bloating, flatulence and loose stool.
Riley P, et al. Cochrane Database of Systematic Reviews, 2015.
Xylitol is toxic to dogs, even in small amounts. Do not leave your gum lying around.