Eating stevia in a highly refined form does have fewer dangers than eating sugar. The FDA approves stevia in this form only. The FDA has not approved whole leaf stevia or crude stevia extracts as a sweetener.
Stevia has fewer calories than sugar. While 2 tablespoons of sugar contain 30 calories and eight carbohydrates, the equivalent amount of stevia only contains five calories and 1 gram of carbohydrates. In addition to the effects on weight via caloric intake, study-based evidence shows that stevia has several other health benefits.
A 2010 study printed in "The Open Obesity Journal" showed that sugar can be linked to the development of Type 2 diabetes, cancer, cavities and inflammatory bowel disease. That same study associated stevia with better glucose levels, fewer cavities, effective antioxidant activity, antibacterial and antiviral properties, and the ability to help with hypertension.