Conducted by psychologists at Purdue University’s Ingestive Behavior Research Center, the study compared rats that ate yogurt containing sugar with rats that ate yogurt sweetened containing saccharin. The rats that ate the yogurt with artificial sweeteners consumed more calories, gained more weight, and had more body fat.

The FDA first approved aspartame, an artificial sweetener added to sodas, in 1974, but rescinded the approval after two studies that showed it caused brain tumors in laboratory animals. Although the FDA never refuted the studies, aspartame was approved again in 1981, and then in 1983 as a soft drink additive.

During the late 1980s the FDA began making visits to companies selling stevia because it was not an approved food additive. The FDA issued an alert on stevia in May 1991 in order to prevent its importation into the U.S., and warned companies not to use stevia. Last August the FDA sent a letter to Hain Celestial Group Inc., the company who makes Celestial Seasonings teas, that its products with stevia contained “an unsafe food additive.”

Ironically stevia is used as a food additive in countries all over the globe, including Japan and China. Coca-Cola Co. and Cargill Inc. use stevia in soft drinks manufactured and sold in other countries. The FDA posted a petition on its website submitted in 1995 which cited more than 900 studies on stevia, and none of the studies indicated the herb is unsafe for human consumption.

“The petition cites over 120 articles about stevia written before 1958, and over 900 articles published to date. In this well-chronicled history of stevia, no author has ever reported any adverse human health consequences associated with consumption of stevia leaf,” the Thomas J. Lipton Company submitted in the 1995 petition.

The 1995 petition also quoted Brazilian scientist Mauro Alvarez as stating, “...as a scientist with over 15 years researching the safety of stevia and of many other plants used as food or food ingredients, I can assure that our conclusions in these various studies indicate that stevia is safe for human consumption as per intended usage, that is, as a sweetener.”

The American Herbal Products Association states on its website that stevia is “a natural product that has been used for at least 400 years as a food product, principally as a sweetener or other flavoring agent. None of this common usage in foods has indicated any evidence of a safety problem. There are no reports of any government agency in any of the above countries indicating any public health concern whatsoever in connection with the use of stevia in foods.”