Stevia is a sweetener and sugar substitute derived from the leaves of the plant species Stevia rebaudiana, native to Brazil and Paraguay. The active compounds are steviol glycosides (mainly stevioside and rebaudioside), which have 30 to 150 times the sweetness of sugar, are heat-stable, pH-stable, and not fermentable. The body does not metabolize the glycosides in stevia, so it contains zero calories, like some artificial sweeteners. Stevia’s taste has a slower onset and longer duration than that of sugar. It has been widely used as a sweetener for decades in Japan.