Stevia comes from an herb in the chrysanthemum family called Stevia rebaudiana. It is native to Paraguay, also grows in Brazil and Argentina, and is cultivated in China. The leaves have been used for centuries by native peoples to make sweet teas, or to sweeten other foods, with no evidence of harm. It is available in the United States, and the European Union as a dietary supplement and is sold here in whole-leaf form or as stevioside, the extracted sweet principle, sold as a granular white powder. The powder has very few calories but is so sweet that to use it, you must dissolve it in water, then dispense the solution by drops. A teaspoon of the liquid is equivalent in sweetness of a whole cup of sugar. Stevia is safe for diabetics and is widely used as a nonnutritive sweetener around the world.
Stevia is a genus of about 240 species of herbs and shrubs in the sunflower family (Asteraceae), native to subtropical and tropical South America and Central America. The species Stevia rebaudiana, commonly known as sweetleaf, sweet leaf, sugarleaf, or simply stevia, is widely grown for its sweet leaves. As a sweetener and sugar substitute, stevia's taste has a slower onset and longer duration than that of sugar, although some of its extracts may have a bitter or licorice-like aftertaste at high concentrations.