No, there's not enough research available to make a concrete assumption of the harmful effects of this supplement. One thing is for sure though, nobody reacts the same, just as no one reacts the exact same way (good or bad) to anything. Why does one person have kidney failure within two weeks and not the next? There was obviously something else involved or else everyone whose taken the supplement would be in a medical center. Fortunately, this is not the case. Without all subjects having the same dietary intake, supplemental intake, medical history and environmental history, any broad generalizations about the subject mean jack! What I'm saying is get checked out if you have concerns. Otherwise, enjoy!