OK, maybe not “toxic”. How about “allergenic”?
I always used to wonder why in the world I got canker sores all the time. They got particularly bad when I was sick or stressed, but even when I was well-rested and stress-free I would often get them. As soon as one would heal I’d get another, and it really was unpleasant.
It turns out I’m sensitive to Sodium Lauryl Sulfate (SLS) an “inactive ingredient” in most toothpastes that causes it to foam up nicely when you brush. Apparently a small but nonzero percentage of the population react poorly to SLS, and canker sores are one of the more common reactions.
It’s difficult to find commercial toothpaste brands that don’t use SLS (although you have to look very closely at the packaging to find it listed) but there are a couple of brands that are SLS-free. I use a Tom’s of Maine brand that has fluoride (don’t tell the Fiendish Fluoridators)…
… but no SLS. Ever since I’ve switched to that brand, I haven’t had any problems. Recently I ran out and had to switch to an SLS-containing brand. Immediately the canker sores returned. As soon as I switched back, they went away.
So if you have problems with canker sores or mouth ulcers, try switching to SLS-free toothpaste and see if that helps. It sure did for me!
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