Stevioside is one of two main extracts from the Stevia rebaudiana plant. By crushing the leaves, soaking them in hot water and utilizing ion exchange, manufacturers can extract stevioside and rebaudioside A from the plant. Stevioside is around 200 to 300 times sweeter than standard table sugar, and has zero calories. In December 2008, the FDA declared stevia sweeteners safe for human consumption as a sweetener.
Antihypertensive Effect
One potential side effect of stevioside is that it might help control high blood pressure, or hypertension. Two double-blind, placebo-controlled studies conducted in China with 280 hypertensive subjects found that stevioside supplementation can reduce high blood pressure and the chances of heart damage from hypertension. However, the New York University Langone Medical Center points out that the subjects in these studies were consuming up to 1,500 mg of stevioside per day, and the controls of the study were not well defined, making the results questionable.
Blood Glucose Control
Registered dietitian Elena Tateo says stevioside might be beneficial for diabetics who are insulin sensitive or insulin resistant. Studies on lab animals showed that stevioside can increase insulin sensitivity. A small human trial demonstrated that stevioside can help control post-meal glucose levels.
Fertility
The Japanese commonly use stevia extracts as a sweetener. Based on traditional use of stevia in that culture to prevent pregnancy, researchers expressed caution in 1985 that stevia extracts such as stevioside might inhibit fertility. Research in the 1990s on animals showed that stevia sweeteners do not negatively impact fertility rates.
Extract Quality
The types of stevioside and other stevia sweeteners approved by the FDA must be highly pure. The processing of the stevia plant will not only yield stevioside, but also plant pigments, carbohydrates and solvent residue in the final product. However, the amount of these impurities found in high-quality stevioside is unlikely to have any negative side effects.
References
- Yeshiva University; Stevia -- Is It Time For Another Look?"; Elena Tateo
- New York University Langone Medical Center: Stevia
- University of Florida; "Stevia Sweeteners -- Another Low-Calorie Option"; May 2002
- American Dietetic Association; "Hot Topic -- Stevia"; June 2009
- Food and Agriculture Organization of the United Nations; "Steviol Glycosides Chemical and Technical Assessment"; Harriet Wallin; 2007
