Stevia is a word both for a plant and for a sweetener extracted from the leaves of that plant. The plant has been grown and used in South America for centuries, and it spread to the rest of the world during the 18th century, when people first began taking the product with them to Europe in large volumes.
In the early 1900s, stevia exploded into popularity in several markets, but the rest of the 20th century was accompanied by vicious battles over it around the world. Some people hail the extract as a healthy, all natural alternative to sugar, while others have health concerns about it, on the basis of laboratory research which suggests the need for further study.
The stevia plant is a perennial shrub native to Paraguay and Brazil. Native Americans in these regions realized that the leaves were sweet, and used them to season teas and other foods. The plant is also sometimes called sweetleaf or sugarleaf, in a reference to the natural sweetness held in the leaves. As Europeans began to explore the foods consumed by Native Americans, they were introduced to stevia.
In the 1930s, chemists in France isolated stevioside, the compound in the leaves that is responsible for their sweetness. This compound is sometimes sold isolated from the leaves in a highly refined form. In other cases, the sweetener is made by crushing or distilling the leaves of the plant to form a powder or a syrup with an intensely sweet flavor.
It has been shown that stevia is much sweeter than other sugars, meaning that only a small amount needs to be used. The body also processes stevia very slowly, which greatly reduces the risk of a sugar high. In addition, it is essentially calorie free, which is why it is popular with dieters. Research also suggests that this sweetener may be safe for diabetics, although diabetics should always consult their doctors about additions to their diet which may alter their blood sugar.
Although stevia sounds like a miracle herb, scientific research may suggest otherwise. Some scientists are concerned that it may be a mutagen, meaning that it could cause cancer. Stevia has also been linked to reproductive malfunction. Some of these studies have been imperfectly performed, but the need for more thorough analysis of the compound has certainly been demonstrated. Proponents suggest that these studies may be part of a larger effort on the part of sugar companies to keep alternatives to sugar off the market, pointing out that stevia is widely used in South America and Asia with no noticeable ill effects. Given the argument over this sweetener, it would appear that more controlled studies are needed.