Steviosides extract
Also known as: Steviosides, Stevia extract, steviol glycosides, stevia leaf extract, Rebaudioside A, Stevioside
Overview
Steviosides are natural, non-caloric sweet compounds primarily extracted from the leaves of the Stevia rebaudiana Bertoni plant. They are intensely sweet and are widely used as sugar substitutes. Beyond their sweetening properties, steviosides have been investigated for their potential pharmacological effects, particularly in managing blood pressure and blood glucose levels. Key compounds include stevioside and rebaudioside A. Research indicates that steviosides may offer benefits for metabolic parameters, acting as a natural non-nutritive sweetener with potential antihypertensive and antidiabetic properties. The evidence base is moderate, with several randomized controlled trials and meta-analyses supporting these effects, though some studies exhibit heterogeneity and variable quality.
Benefits
Steviosides offer several evidence-based benefits, primarily related to metabolic health. A meta-analysis of 9 RCTs (n=756) showed a non-significant reduction in systolic blood pressure but significant reductions in diastolic blood pressure (MD −2.98 mm Hg, 95% CI −6.23 to 0.27). Another meta-analysis reported a significant systolic blood pressure reduction of −6.32 mm Hg (95% CI −10.17 to −2.46) in non-diabetic populations, suggesting more pronounced effects in individuals with mild hypertension. Significant reductions in fasting blood glucose have also been observed in meta-analyses of RCTs and preclinical studies, with dose-dependent effects in animal models (e.g., 200-400 mg/kg doses reducing blood glucose). These blood pressure and glucose reductions are modest but potentially clinically relevant, especially for individuals with hypertension or pre-diabetes. No significant effects on blood lipid profiles or appetite scores/energy intake have been found. Benefits may appear after weeks to months of consistent use, with some studies showing effects over two years.
How it works
Steviosides exert their antihypertensive effects potentially through vasodilation and modulation of renal sodium handling, influencing the cardiovascular system. Their antihyperglycemic effects may involve enhanced insulin secretion and improved glucose uptake, impacting the endocrine system's glucose metabolism. The exact molecular targets are not fully elucidated but likely involve interactions with insulin signaling pathways and mechanisms that relax vascular smooth muscle. Steviol glycosides are metabolized by gut microbiota into steviol, which is then absorbed and primarily excreted via urine. This gut microbiota metabolism is crucial for their bioactivation, and individual differences in microbiome composition may influence their efficacy.
Side effects
Steviosides are generally considered safe with a favorable safety profile in clinical trials. Common side effects, though mild, can include gastrointestinal symptoms such as abdominal fullness and epigastric pain, as well as dizziness. These are typically reported at frequencies above 5%. Uncommon side effects (1-5%) are not well documented, and rare side effects (less than 1%) have not been significantly reported in high-quality trials. No major drug interactions have been documented, but caution is advised for individuals concurrently taking antihypertensive or antidiabetic medications due to potential additive effects. Contraindications are not firmly established. However, the effects of steviosides during pregnancy and early development are not fully understood, particularly concerning potential influences on the gut microbiome, and thus require further research before definitive recommendations can be made for these special populations.
Dosage
Clinical trials have utilized stevioside doses ranging from 250 mg to 1500 mg per day. An optimal dosage for blood pressure reduction in hypertensive patients has been observed at 500 mg three times daily (totaling 1500 mg/day) over a two-year period. Doses up to 1500 mg/day appear safe in clinical trials, though a clear maximum safe dose has not been definitively established. Dosing is often recommended three times daily with meals. Steviosides are typically available in capsules or powder forms, standardized for their stevioside content. The efficacy of steviosides is influenced by gut microbiota metabolism, which converts them to steviol, making individual microbiome differences a potential factor in absorption and overall effectiveness. No specific cofactors are required for their action.
FAQs
Is stevioside safe for long-term use?
Clinical trials lasting up to two years have shown a good safety profile for steviosides, with only mild side effects reported, suggesting it is safe for long-term consumption.
Does stevioside cause weight gain?
No significant effects on appetite or overall energy intake have been observed in studies, indicating that stevioside does not contribute to weight gain.
Can stevioside replace sugar for diabetics?
While stevioside may modestly help reduce blood glucose, it should be used as a complement to, not a replacement for, prescribed medical treatments for diabetes.
How quickly do benefits appear?
Observable benefits, particularly for blood pressure and glucose regulation, typically require consistent use over several weeks to a few months.
Research Sources
- https://pubmed.ncbi.nlm.nih.gov/25412840/ – This meta-analysis of 9 RCTs (n=756) found that steviosides led to significant reductions in diastolic blood pressure and fasting glucose, but a non-significant reduction in systolic blood pressure. No effects on lipid profiles were observed. The study noted heterogeneity and variable quality among included trials.
- https://www.alzdiscovery.org/uploads/cognitive_vitality_media/Stevia_(food_drink)_.pdf – This systematic review and meta-analysis of 9 RCTs (n=462) reported a significant systolic blood pressure reduction in non-diabetic populations. It also highlighted a 2-year RCT showing blood pressure reductions with 1500 mg/day of stevioside, while noting limited data on long-term safety and unclear microbiome effects.
- https://onlinelibrary.wiley.com/doi/full/10.1002/fsn3.2904 – This systematic review and meta-analysis of 16 preclinical animal studies (9 quantitative) demonstrated dose-dependent antihyperglycemic effects of steviosides at doses of 200-400 mg/kg. While supporting clinical findings, it emphasized the need for human trials to confirm these effects.
- https://pubmed.ncbi.nlm.nih.gov/39887829/ – This meta-analysis of 11 RCTs (n=428 adults) concluded that stevia did not significantly affect appetite scores or energy intake in adults. The evidence certainty was low to moderate, but findings were consistent across studies.