A dry mouth is a well known cause of bad breath, which is one reason why many people choose to brush their teeth and rinse their mouths regularly. However, an ingredient in some oral health products may lead consumers to unwittingly trade parched palates for a more painful plight.
If you look at the back of a typical tube of toothpaste, you may notice an ingredient called sodium lauryl sulfate (SLS). This compound is included in many toothpastes and mouthrinses for one basic reason: it foams.
SLS is a surfactant, detergent and emulsifier, though what it does depends on its concentration in a solution. Essentially, though, this substance is something like soap. It helps toothpaste bubble up between your teeth.
Unfortunately, it can also irritate the delicate skin inside your mouth. If you've ever had a canker sore - which is like a painful cold sore that occurs inside your mouth - its possible that it came from exposure to SLS. Other causes of such sores include minor mouth injuries or irritation from dental hardware.
That said, not all toothpastes or rinses contain this substance. If you have trouble with canker sores or simply don't want to develop them, you may consider looking into SLS-free specialty breath freshening products.