Whole Stevia Leaf and Crude Extract are not the Same as High Purity Stevia Leaf Extract.
San Antonio TX. For centuries the Guaraní people from South America have used dried stevia leaves to sweeten their drinks and as medicine. Today, crude stevia extractsare still sold as dietary supplements in some countries; however, according to the Global Stevia Institute (GSI), it is only the high purity stevia leaf extract that has been evaluated and approved for use as an ingredient in food and beverages by the world’s leading regulatory agencies.
The sweet compounds of the stevia plant – called steviol glycosides, responsible for its sweet taste –can be extracted from the leaf and can be used in products to achieve a very similar taste of sucrose. The purification process of stevia, according to the GSI, includes the following steps: The dried leaves are steeped in water in order to release their sweet tasting steviol glycoside compounds –among them the rebaudioside A (Reb A) and stevioside. Next, the liquid is filtered and separated from the plant material. Then the extract is purified and dried to obtain high purity stevia leaf extract with the same sweet components as found in stevia’s natural leaves. These components, the steviol glycosides, are what food and beverage manufacturers use in their products.
According to the European Food Safety Authority Journal (EFSA Journal), the World Health Organization’s Joint Expert Committee on Food Additive (JECFA) reviewed the safety of steviol glycosides in 2000, 2005, 2006, 2007, and 2009 and established an ADI for steviol glycosides (expressed as steviol equivalents) of 4 mg/kg bw/day. Results of toxicology studies on either stevioside or rebaudioside A are applicable for the safety assessment of steviol glycosides as both rebaudioside A and stevioside are metabolised and excreted by similar pathways, with steviol being the common metabolite for both.
The EFSA Journal says that metabolic studies with steviol glycosides in animals and humans demonstrated that intact steviol glycosides are poorly absorbed after oral exposure but that they are hydrolysed by the microflora in the colon to steviol. A large amount of steviol is absorbed; the rest is excreted in the faeces. In the liver, steviol undergoes conjugation with glucuronic acid to form steviol glucuronide. The only inter-species difference is that the glucuronide is excreted primarily via the urine in humans and via the bile in rats. No accumulation of steviol glycosidederivatives occurs in the body. Besides steviol glucuronide, no other derivatives could be detected in the urine of humans exposed orally to steviol glycosides.
This fact makes high purity stevia leaf extract a safe product for human consumption, with no-calorie impact. The whole stevia leaf or the crude stevia extracts are not approved for use by international food and drinks authorities.
- The Global Stevia Institue http://globalsteviainstitute.com/health-professionals/safety-food-policy/safety/
- European Food Safety Authority Journal: Scientific Opinion on the safety of steviol glycosides for the proposed uses as a food additive http://www.efsa.europa.eu/en/efsajournal/pub/1537
SVETIA® Calorie – Free Sweetener is made with cane sugar and stevia extract. One packet of SVETIA® contains only one gram of carbohydrates. People with diabetes are advised to check with their registered dietitian or physician.