Asked by: Joyce Burley, Hull
Toothpaste needs something to mask the soapy taste of the detergents that create the foam when you brush. Sugar is out, for obvious reasons, but sweeteners such as xylitol or sorbitol do a pretty good job.
These chemicals attract water molecules, so they have the added benefit of keeping water locked in the toothpaste, preventing it from drying out. Research also suggests that xylitol can help to kill off plaque bacteria in the mouth by starving them of sugar.
Read more:
- What’s in toothpaste?
- Why does orange juice taste bad after tooth brushing?
- How hard is tooth enamel compared to other materials?
- Does flossing your teeth really make a difference?
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