Stevia (Steviol Glycosides)
Last reviewed October 18, 2026 · Evidence strength: Moderate · How we grade evidence
In plain words: Purified stevia is one of the best-studied sugar substitutes and looks safe at normal amounts. A month-long trial found it didn't upset gut bacteria or blood markers. Check the label, though: many "stevia" packets are mostly erythritol or dextrose.
Also listed on labels as: Stevia, Stevia leaf extract, Steviol glycosides, Rebaudioside A (Reb A), Reb M, Truvia, PureVia, E960
What is it, and why is it in food?
Stevia sweeteners are purified extracts (steviol glycosides) from the leaves of the stevia plant. They're 200 to 400 times sweeter than sugar. Newer types like Reb M are often made by fermentation or enzyme processing, so "natural" is partly marketing. You'll find stevia in drinks, yogurts, protein bars and tabletop packets.
What does the science say?
| The popular claim | "Stevia is a safe, natural zero-calorie sweetener and a good sugar substitute." (Endorsed by Dr. Steven Gundry and Dr. Eric Berg.) |
| Our verdict on that claim | Supported |
| Evidence strength | Moderate: randomized trials and safety reviews agree; few long-term studies. |
| Kinds of studies | Randomized trials, review of trials, EU and FDA safety reviews |
- Gut and heart markers: In a 4-week trial, a daily drink with stevia (at 25% of the safe limit) didn't change gut bacteria, gut fatty acids or fasting heart and metabolism markers compared with a sugar drink. The sugar group's BMI went up slightly.1
- Blood sugar: A 2024 review found stevia lowered blood sugar a little (about 4 mg/dL), with low certainty, and no effect on HbA1c.2
- A caveat: In the 2022 sweetener trial, stevia changed the makeup of gut bacteria but didn't significantly worsen blood sugar.3
What do regulators say?
- EFSA found steviol glycosides don't cause cancer, DNA damage or reproductive harm, with a safe daily limit of 4 mg per kg of body weight.4 In 2026 it evaluated Reb M made by enzyme conversion.5
- US: high-purity extracts are used under FDA GRAS notices. Whole-leaf and crude stevia aren't approved as food additives.
Who should be careful?
- Blends: if a stevia product's first ingredient is erythritol, see our Erythritol guide, especially for anyone with heart disease or clotting risk.
- Some people dislike the aftertaste. That's a taste issue, not a safety one.
How common is it in US foods?
In our check of USDA's Branded Foods database, 7,928 of 438,129 US packaged foods with an ingredient list name stevia or steviol glycosides (about 1.8%, or roughly 1 in 55).6 It shows up most often in: snack, energy & granola bars (762); energy, protein & muscle recovery drinks (599); powdered drinks (598); yogurt (529); soda (527). Protein and granola bars, protein drinks and drink mixes lead the list. These are label records companies sent to USDA, mostly in 2021 to 2023, so some products have changed since. Counts come from a text match of ingredient lists and are approximate.
Swaps and tips for families
- Pick pure stevia drops or packets that list only stevia (and maybe a little inulin), rather than erythritol blends.
- Use it to step down from sugary drinks, then aim for unsweetened.
Beyond the plate: related non-food exposures
None notable.
Frequently asked questions
Is stevia safe?
Yes, purified stevia extracts are among the best-studied sweeteners, with safety reviews in the US and Europe and reassuring human trials.
Is stevia better than sugar?
It has no calories and doesn't raise blood sugar like sugar does. A month-long trial found no harm to gut bacteria compared with sugar.
Why does my stevia contain erythritol?
Stevia is so sweet that companies add bulk. Erythritol and dextrose are the most common fillers, so read the label.
Is stevia natural?
It comes from a plant, but purified extracts, and especially Reb M, involve heavy processing or fermentation.
Related guides
Sources
Every source below was checked against PubMed, the publisher or the official page by our research team in October 2026.
- Comparison of a Daily Steviol Glycoside Beverage compared with a Sucrose Beverage for Four Weeks on Gut Microbiome in Healthy Adults. The Journal of nutrition, 2024. PubMed 38408729 · doi:10.1016/j.tjnut.2024.01.032
- Effect of stevia on blood glucose and HbA1C: A meta-analysis. Diabetes & metabolic syndrome, 2024. PubMed 39098209 · doi:10.1016/j.dsx.2024.103092
- Personalized microbiome-driven effects of non-nutritive sweeteners on human glucose tolerance. Cell, 2022. PubMed 35987213 · doi:10.1016/j.cell.2022.07.016
- Scientific Opinion on the safety of steviol glycosides for the proposed uses as a food additive. EFSA Journal, 2010. doi:10.2903/j.efsa.2010.1537
- Safety evaluation of the food additive rebaudioside M produced via enzymatic conversion of purified steviol glycosides leaf extracts. EFSA journal. European Food Safety Authority, 2026. PubMed 42757032 · doi:10.2903/j.efsa.2026.10232
- FoodData Central, Branded Foods dataset (release 2026-04-30). U.S. Department of Agriculture, Agricultural Research Service, 2026. Link
This guide is for general education. It is not medical advice and does not replace advice from your doctor, pediatrician, allergist or registered dietitian. If you think you or your child reacted to a food, talk to a health professional. Research changes; we review these pages when new evidence or rules come out. Last reviewed October 18, 2026. Spotted an error? Email [email protected].