You're wrong. First of all, sugar may be unhealthy in excess but it is still less harmful than any artificial sweetener and most natural ones. There's a reason you can taste sweetness and that's because sugar is an important source of energy for most land animals. The problem is people in modern times are accustomed to extreme levels of it that aren't even possible in nature. The solution to this is gradually reducing sugar intake, not replacing it with toxic chemicals or exotic jungle herbs. Stevia was indeed used as (somewhat unreliable) birth control by Paraguayan natives and Japan's abysmal fertility clearly shows they were on to something.