Acesulfame K is not metabolized by the body and is excreted unchanged.
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More than 90 studies have demonstrated the safety of acesulfame K. The U.S. Food and Drug Administration permitted the use of acesulfame K after evaluating numerous studies and determining it is safe for its intended use.
The FDA approved acesulfame K for use in liquid non-alcoholic beverages (soft drinks) on July 6, 1998. FDA has reaffirmed acesulfame K's safety on nine separate occasions by broadening its approval. A general use approval was grated by the FDA in December of 2003.
The Joint Expert Committee on Food Additives (JECFA), the scientific advisory body to the World Health Organization and the Food and Agriculture Organization of the United Nations, reviewed the available research on acesulfame K and concluded that it is safe. JECFA has also established an ADI of 15 mg/kg of body weight.
The Scientific Committee for Food of the European Union published a comprehensive assessment of sweetening agents in 1985. This committee of toxicological experts from the EU member countries accepted acesulfame K for use in foods and beverages. Acesulfame K has been used in Europe since 1983, and in the U.S. since 1988, with no known documented adverse health effects.
Source:
http://www.caloriecontrol.org/acesulf.html
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How does the body handle acesulfame potassium?
Acesulfame potassium is not metabolized or stored in the body. After it is consumed, it is quickly absorbed by the body and then rapidly excreted unchanged.
Is acesulfame potassium safe?
Yes. Acesulfame potassium is safe and suitable for all segments of the population. The FDA, which is the governmental agency responsible for ensuring the safety of all foods, has approved acesulfame potassium for use in numerous food products on eight separate occasions since 1988. The agency based its decisions on a large body of scientific evidence that demonstrates the safety of the ingredient.
Have other regulatory bodies reviewed the safety of acesulfame potassium?
Yes. Acesulfame potassium has been approved for use in about 90 countries. For example, it is widely used in foods and beverages in the United Kingdom, Germany, Australia and Canada. In addition, acesulfame potassium has been reviewed and found safe by the Joint Expert Committee on Food Additives of the World Health Organization and the Scientific Committee for Food of the European Union.
Can acesulfame potassium cause cancer?
No. Acesulfame potassium has been thoroughly tested in several long-term animal studies. The tests, which used amounts of the ingredient that are far higher than a person would normally consume, clearly found no evidence of cancer or tumors.
Source:
http://www.ific.org/publications/brochures/acekbroch.cfm