A few years ago I was at a seminar with Dr. Scott Connolly founder of MET-Rx (and in all seriousness one of the brightest guys to ever enter the industry) and he said Clen will screw up your thyroid. Even when not used with T3 or any other thyroid drugs he said it messes it up permanently. He explained the mechanism but I can't remember the specifics. I got off the stuff that day! Anybody else know if this is accurate?