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Published on: September 1, 2016
Subchronic toxicity of rebaudioside A
Leslie L Curry1, Ashley Roberts
1Cargill, Incorporated, 15407 McGinty Road, W. MS 163, Wayzata, MN 55391, United States. Leslie_Curry@cargill.com
Summary
Rebaudioside A, a stevia sweetener, showed no adverse effects in Wistar rats up to 100,000 ppm in a 4-week oral toxicity study. A 13-week study established the No Observed Adverse Effect Level (NOAEL) at 50,000 ppm.
Area of Science:
- Toxicology
- Food Science
- Pharmacology
Background:
- Stevia rebaudiana leaf extract is a natural, zero-calorie sweetener.
- Rebaudioside A is a major sweet glycoside component of stevia.
- Assessing the safety of food additives is crucial for public health.
Purpose of the Study:
- To evaluate the oral toxicity of rebaudioside A in Wistar rats.
- To determine the No Observed Adverse Effect Level (NOAEL) for rebaudioside A.
- To identify any potential treatment-related adverse effects.
Main Methods:
- Two oral toxicity studies were conducted: a 4-week and a 13-week study.
- Wistar rats were administered varying dietary concentrations of rebaudioside A.
- Comprehensive toxicological assessments included clinical pathology, organ weights, histopathology, and functional observational battery tests.
Main Results:
- The NOAEL was determined to be 100,000 ppm in the 4-week study.
- In the 13-week study, the NOAEL was 50,000 ppm (approx. 4161-4645 mg/kg/day).
- Minor effects like reduced body weight gain and altered bile acid metabolism were observed at high doses, attributed to taste aversion and physiological adaptation.
Conclusions:
- Rebaudioside A demonstrates a favorable safety profile in oral toxicity studies.
- No significant treatment-related adverse findings were observed in major organs, including testes and kidneys.
- The established NOAELs support the safety of rebaudioside A as a food sweetener.
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