Benefits
Natural Sugar Substitute
Steviol glycosides are intensely sweet but supply no calories, so they can be used in place of sugar. This is a property of stevia sweeteners in general and has not been tested for Vitosa specifically. Swapping sugar for stevia lowers the sugar in a food; it is not itself a treatment for diabetes or for excess weight.
No Glycemic Impact
In human crossover trials, stevia preloads did not raise blood sugar or insulin after a meal the way sugar did (PMID 20303371, PMID 31842388), and a systematic review and network meta-analysis of non-nutritively sweetened drinks found the same (PMID 36839408). This means stevia does not add to blood sugar when it replaces sugar. It does not mean stevia lowers blood sugar. FDA treats purified steviol glycosides as generally recognized as safe (GRAS).
Taste (Manufacturer Claim, Not a Health Benefit)
The manufacturer says Vitosa is refined to reduce the bitter, licorice-like aftertaste that some people notice with stevia. No published taste comparison of Vitosa against other stevia products was found, and taste is not a health benefit.
Heat-Stable for Cooking and Beverages
Steviol glycosides hold their sweetness when heated, so they can be used in baking and in processed drinks. This is a handling property of the ingredient for manufacturers, not a health effect for you.
Comes From a Plant Rather Than a Lab
Steviol glycosides are extracted from the stevia leaf rather than made synthetically like sucralose, aspartame or saccharin. Coming from a plant does not by itself make a sweetener healthier. The one cited study that compared them head to head (PMID 20303371) looked only at blood sugar, insulin and fullness after a single meal, and stevia and aspartame behaved similarly.
Mechanism of action
Steviol Glycoside Sweetness
Stevia leaves contain steviol glycosides — naturally intensely sweet, roughly 200 to 400 times sweeter than table sugar. The body does not use them for energy, so they add no calories.
Bitter Receptor Considerations
Some steviol glycosides activate bitter taste receptors on the tongue, which is where stevia's aftertaste comes from. BGG says its purification lowers the bitter-tasting compounds in Vitosa. That is a manufacturer claim; no published measurement or comparison was found.
No Insulin Response
In the cited human trials, stevia preloads did not raise insulin after a meal the way sugar did (PMID 20303371). 'Appropriate for diabetic dietary management' overstates this: replacing sugar with stevia is a dietary swap, not a treatment for diabetes, and people with diabetes should follow their own clinician's advice.
Clinical trials
This entry summarises several separate studies of generic stevia extract and purified steviol glycosides. None of them tested Vitosa. The study linked below is a randomised controlled trial of stevia in people already diagnosed with type 2 diabetes (PMID 32257884).
Healthy adults in the short single-meal crossover trials (PMID 20303371, PMID 31842388); people already diagnosed with type 2 diabetes in PMID 32257884; 174 Chinese adults with mild essential hypertension in PMID 14693305.
In healthy adults, stevia did not raise blood sugar or insulin after a meal the way sugar did. In the two-year trial in people with mild high blood pressure, 500 mg of purified stevioside three times daily (1,500 mg a day) lowered average systolic pressure from about 150 to about 140 mmHg and diastolic from about 95 to about 89 mmHg compared with placebo. That was a drug-style dose given to diagnosed patients over two years, and it is not a reason to expect any blood pressure change from sweetening a drink.