Stevia extract may cause mild side effects such as nausea and a feeling of fullness in some patients, explains Mayo Clinic. This natural plant extract is considered a non-nutritive sweetener and is generally recognized as safe by the Food and Drug Administration.
Only refined stevia extract is approved for use as a food additive by the FDA, explains Mayo Clinic. It is commonly used by people who are trying to lose weight. Whole-leaf stevia and crude stevia extract have not been approved by the FDA as of 2014, mainly because of concerns about product safety. These products may have negative effects on blood sugar balance, the reproductive system and the cardiovascular system.
Stevia was first discovered more than 200 years ago in South America, according to the Global Stevia Institute. It was used by indigenous people to sweeten beverages. In the 1930s, French chemists isolated the sweet components of the plant, and in the 1970s, stevia extracts were used commercially in Japan. Stevia extract was approved by the FDA in 2008, and it has increased in popularity since then. Stevia extracts are now found in sodas, sports drinks and sweetener packets, according to WebMD. Baking blends containing stevia extract are also available.