A man shows stevia plant seeds, known as

A man shows stevia plant seeds, known as “sweet herb”, or “ka´a he´e” in the native Guarani language, in Ypacaray, 34 kms of Asuncion, Paraguay on October 22, 2009. Stevia is used for its medicinal purposes, which include treatment for heartburn, obesity and hypertension, as well as a natural sweetener for diabetics. AFP PHOTO/Norberto Duarte (Photo credit should read NORBERTO DUARTE/AFP/Getty Images)