I will give you my take on Truvia for what it's worth but please keep in mind I am a Holistic Nutritionist.
Stevia is from a flower. It is totally natural and hundreds of times sweeter than sugar. Until recently it has been banned in the US by the FDA as a sweetener (it was actually illegal to call it a sugar substitute or natural sweetener) because it could not be patented by any pharmaceutical company because it comes from a plant - not made in a lab like aspartame.
Stevia has a slight aftertaste that some liken to licorice and can be slightly bitter if you use too much. So the oh-so-clever pharmaceutical companies (I hope you are reading that with a heavy dose of sarcasm!!!!) realized that if they could alter the Stevia and eliminate that aftertaste, they could patent it. Ta da - Truvia.
Am I cynical about Pharmaceutical companies? You bet!!!!
Do I like natural products that have been altered in a lab? No Way!!!
This is disgusting to me. They have taken a perfectly good sweetener from nature (legal in Canada, by the way) and for the sake of money, screwed it up in a lab.
Is Truvia harmful? I have no idea, but I sticking with natural Stevia, thanks. You can find the real Stevia on Amazon, thank goodness.
http://astore.amazon.com/steviasweetener-20