Steviol glycosides side effects, structure stevioside
February 1 2017
Stevia rebaudiana leaves contain non-cariogenic and non-caloric sweeteners (steviol-glycosides) whose consumption could exert beneficial effects on human health. Steviol-glycosides are considered safe; nonetheless, studies on animals highlighted adverse effects attributed to the aglycone steviol.
About steviol glycosides
The sweet components of the stevia leaf. There are various kinds of steviol glycosides, but the two most abundant types are stevioside and rebaudioside A. Other steviol glycosides include stevioside, rebaudioside A, rebaudioside C, dulcoside A, rubusoside, steviolbioside, rebaudioside B, rebaudioside D and rebaudioside F.
About rebaudioside A
The best-tasting of the steviol glycosides found in the stevia plant. Rebaudioside A is almost identical in chemical structure to stevioside, and the body breaks it down into the same basic parts. This means that the extensive body of safety data on stevioside can be applied to rebaudioside A.
Rebiana is a 97% pure form of rebaudioside A. It is the first high-purity, well-characterised form of rebaudioside A.
Blood sugar, diabetes
Steviol effect, a glycoside of Stevia rebaudiana, on glucose clearances in rats.
Braz J Biol. 2009.
Stevia rebaudiana, a South American plant normally used as a natural herbal sweetener, has been suggested as exerting beneficial effects on human health, including as an antihypertensive and antihyperglycemic. The present experiment was undertaken to evaluate the renal excretion of steviol, the aglycone of several natural products extracted from the leaves of S. rebaudiana, and to clarify the actual participation of this compound on the renal excretion of glucose in rats, which has been previously suggested as the preferential action of steviol on the Na+-glucose renal tubular transport system. Steviol was obtained by enzymatic hydrolysis of stevioside with pectinase. Thirty normal male Wistar rats weighing 345 g were used. After a control period, steviol was infused iv at three doses (0.5, 1.0 and 3.0 mg.kg-1/h), according to classical clearance techniques. During all the experiments no significant changes in inulin clearance (Cin) and p-aminohipuric acid clearance (C PAH) were observed. Administration of steviol resulted in a statistically significant increase in the fractional sodium excretion (FeNa+), fractional potassium excretion (FeK+), urinary flow as percent of glomerular filtration rate (V/GFR) and glucose clearance (C G) when compared to controls, but these effects were absent with the dose of 0.5 mg.kg-1/h. The steviol clearance (C S) was higher than the Cin and lower than the C PAH at all the doses employed in this study. The data suggest that steviol is secreted by renal tubular epithelium, causing diuresis, natriuresis, kaliuresis and a fall in renal tubular reabsorption of glucose.
Safety, side effects
The European Food Safety Authority (EFSA) today published a scientific opinion which confirms that steviol glycosides, sweeteners extracted from the stevia plant, are safe for use in foods and beverages and establishes an Acceptable Daily Intake (ADI) for their safe consumption. In the published opinion, EFSA's Panel on Food Additives and Nutrient Sources Added to Foods (ANS) concludes that, considering the available toxicity data, "steviol glycosides complying with JECFA specifications are not carcinogenic, genotoxic or associated with any reproductive / development toxicity." The ANS Panel also establishes an ADI for steviol glycosides, expressed as steviol equivalents, of 4 mg/kg bw/day, the same ADI as previously established by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). The opinion is based on a rigorous safety assessment by EFSA's ANS expert panel of the scientific dossiers submitted by several applicants including Cargill, maker of Truvia sweetener, a zero-calorie sweetener derived from the leaf of the stevia plant. Truvia tabletop sweetener, the U.S. market leader in the new category of stevia-based sweeteners is made with rebiana, which is 97% pure rebaudioside A, the best-tasting part of the stevia leaf and one of the steviol glycosides assessed by EFSA.