Sodium lauryl sulfate (SLS) & Tooth paste

I have always had mouth ulcers - on & off and somewhere I read that Sodium lauryl sulfate (SLS) could be the cause. I roamed the super markets and found that 99% of tooth pastes contains this ingredient. Finally I got hold of a Herbal tooth paste and assumed that this may not have it since only a few herbal ingredients were listed. Well I didnt have the ulcers for a long time. That is when we decided to paint our flat and my tooth paste was packed somewhere and I was forced to use the normal one. And it started again.. those ulcers...

So I guess for a few of us it is better to stay away from SLS.