I don't. But yet I still use it...
No offense to V-Rap (who I respect greatly), but doctors tend to want scientific studies before believing anything (with good reason). The trouble is that most things proven to be good/bad for you were knwon to be so by "alternative" peeps for ages beforehand.
I think that Nutrasweet (which is banned in Canada & Oz, I believe) is effectively a slow acting poison. The truth will come out eventually...