sure, it sounds crazy. but it's true: toothpaste can aggravate and create acne, and is particularly troublesome for those who break out around the mouth.
in fact, it was the last product sS's very own esthetician christine changed in her product regimen when she was still a client of kim's in 2008. we had purged everything out of her skin and she was pretty much clear all over (she had crazy inflamed cystic acne going on, believe it or not), but had some trouble clearing up around the mouth.
then, our soon-to-be-sS-miracle-worker did some detective work found SLS in her toothpaste - which was actually the last ingredient in the formulation! she switched to an acne safe one (kiss my face), and has been clear ever since.
since then, we've whole-heartedly recommended only 1 acne-safe toothpaste - from kiss my face (available at sS for $5.50 - the same price as rainbow grocery).
recently, a couple of clients have alerted us to other safe ones on the market - nature's gate is a safe one.
and... although sensodyne's pronamel gentle whitening toothpaste's ingredients look safe, christine tested it for months and it eventually broke her out. sneaky! so to be absolutely 100% sure something is safe, we still have to test it out for at least 6 months.