Up to now, the U.S. Food and Drug Administration doesn’t approved Stevia use as a food additive with an excuse that there is no proof or official scientific experiment to warranty about the side-effect of Stevia.

Up to now, the U.S. Food and Drug Administration doesn’t approved Stevia use as a food additive with an excuse that there is no proof or official scientific experiment to warranty about the side-effect of Stevia.
In 1994 Dietary Supplement Health and Education Act forced the FDA in 1995 to revise its stance to permit stevia to be used as a dietary supplement, although not as a food additive — a position that stevia proponents regard as contradictory because it simultaneously labels stevia as safe and unsafe, depending on how it is sold. Canada Health adopted the same decision as US Government to please the publicity and food processors. The Scientific Committee on Food for the European Commission also didn’t state the approval of stevia or stevioside as a food additive since “there are no satisfactory data to support the safe use of these products [stevia plants and leaves]”
The Joint FAO/WHO Expert Committee on Food Additives (JECFA) reviewed stevioside in 1998, but could not quantify an Acceptable Daily Intake (ADI) because of inadequate data on the composition and safety of stevioside. The Committee recommended that further studies be done on the metabolism of stevioside in humans and on the potential genetic effects of steviol (a metabolite of stevioside).
Center for Science in the Public Interest (CSPI) is a Washington, D.C.-based non-profit watchdog and consumer advocacy group focusing on nutritional education and awareness. ts guidelines include detailed nutrition labeling, a prohibition on trans fats additives, and reducing the amount of sodium in processed foods. They also did their own evaluation based on all sources of information and concluded not to put Stevia into food additives after all.
The other expert, Ryan Huxtable, a University of Arizona toxicologist, found Kinghorn's 1992 safety review to be extremely competent and said in a letter to the Herb Research Foundation that based on it, "there seems little scientific reason for the FDA not to approve the use of Stevia extracts in the U.S.

• - Reproductive problems. Stevioside “seems to affect the male reproductive organ system,” European scientists concluded last year. When male rats were fed high doses of stevioside for 22 months, sperm production was reduced, the weight of seminal vesicles (which produce seminal fluid) declined, and there was an increase in cell proliferation in their testicles, which could cause infertility or other problems.1 And when female hamsters were fed large amounts of a derivative of stevioside called steviol, they had fewer and smaller offspring.2 Would small amounts of stevia also cause reproductive problems? No one knows.
• - Cancer. In the laboratory, steviol can be converted into a mutagenic compound, which may promote cancer by causing mutations in the cells’ genetic material (DNA). “We don’t know if the conversion of stevioside to steviol to a mutagen happens in humans,” says Huxtable. “It’s probably a minor issue, but it clearly needs to be resolved.”
• - Energy metabolism. Very large amounts of stevioside can interfere with the absorption of carbohydrates in animals and disrupt the conversion of food into energy within cells. “This may be of particular concern for children,” says Huxtable.