In general, stevia and white ("original") sugar are very, very damaging to the human mind and the human nervous system. Large amounts are especially harmful and not recommended at all. Pure cane sugar, the brown kind, is very good in moderate amounts. All other kinds are fully artificial and toxic to the body.
I have never heard about this natural sweetener, Stevia. This is the first time that I have know this organic source of sweetener. As I search, I have that there three types of Stevia and their respective effects to the body of the user/consumer. The green leaf of Stevia has a better effect to the consumer. The other one is Stevia extract which is 200 time sweeter than sugar. And last type is altered or processed Stevia just like Truvia. It has no good effect to the consumer due to GMO ingredients. I have no idea if this kind of natural sweetener is grown in our country or place which sugar is the one of the major income-earners by the rich people like haciendero as we call it in our local dialect.
Some other natural sweeteners (but not sure about the organic thing)are Raw Honey which also has a lot of antioxidants in it as well. Date Paste is another one and is good for baking. Coconut sugar is yet another natural one,and also Maple Syrup is good for glazes on cookies or cakes.
Personally, I am a huge fan of Agave nectar. It takes very little and packs a huge punch! I have had no digestive issues since switching from Sugar in the Raw 8 months ago. It's fairly inexpensive and can be found in most health food stores and supermarkets.
Even though i have only been using them for a few months, i can say that they are almost as good as the regular sweetener and considering the health benefits they are a must.