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In A Nutshell
- One drink, a huge spike. In Cleveland Clinic research, 30 grams of erythritol, about what some sugar-free drinks and desserts contain, raised blood levels of the sweetener roughly a thousandfold, and they stayed high for two to three days, lead researcher Stanley Hazen told CNN.
- The heart link came first. In the team’s 2023 study in Nature Medicine, people with the highest blood levels of erythritol had about twice the risk of a heart attack or stroke over three years as those with the lowest.
- Brain blood vessels are the newest concern. A 2025 University of Colorado Boulder lab study found that a drink’s worth of erythritol changed human brain blood vessel cells in ways linked to stroke risk.
- The evidence is still building. These studies show associations and lab effects, not proof that erythritol causes heart attacks or strokes in everyday use. Larger studies in people are still needed.
Check the label on a sugar-free soda, a keto ice cream or a low-carb protein bar, and there is a good chance you will find erythritol. It tastes like sugar, has almost no calories and barely moves blood sugar, which is why it became a favorite of people watching their weight or managing diabetes.
Over the past three years, though, a series of studies has raised a question nobody expected: what happens in your blood after you eat or drink it? The research does not prove the sweetener is dangerous, but it has shifted the conversation enough that cardiologists and nutrition researchers are paying close attention. Here is what the studies actually found, and what they do not show.
What Is Erythritol, And Why Is It Everywhere?
It is a sugar alcohol that looks, tastes and bakes like sugar.
Erythritol is about 80 percent as sweet as table sugar and has a negligible effect on insulin. “Erythritol looks like sugar, it tastes like sugar, and you can bake with it,” said Stanley Hazen, who directs the Cleveland Clinic’s Center for Cardiovascular Diagnostics and Prevention. The body makes small amounts of it naturally, but the levels measured in recent studies were far higher than the body produces on its own.
StudyFinds has followed this research for years, and each new study has added a piece to the picture.
What Did The Heart Studies Find?
Higher blood levels were linked to more heart attacks and strokes, and to stickier platelets.
The first major signal came in 2023. In a study of more than 4,000 people published in Nature Medicine, those whose blood levels of erythritol were in the top 25 percent had about a two-fold higher risk of heart attack and stroke over the next three years than those in the bottom 25 percent. The link was seen in people who already had risk factors such as diabetes.
The same team then tested what a single serving does. “Thirty grams was enough to make blood levels of erythritol go up a thousandfold,” Hazen said. “It remained elevated above the threshold necessary to trigger and heighten clotting risk for the following two to three days.” In a follow-up study in healthy volunteers, a drink sweetened with erythritol made blood platelets more reactive, compared with a drink sweetened with regular sugar.
Why Are Researchers Now Looking At The Brain?
A lab study suggests erythritol may affect the cells that line the brain’s blood vessels.
In 2025, researchers at the University of Colorado Boulder treated human brain blood vessel cells for three hours with about the amount of erythritol found in a typical sugar-free beverage. The cells produced less nitric oxide, a molecule that relaxes and widens blood vessels, and more endothelin-1, a protein that narrows them. When the scientists triggered clotting, the cells’ release of t-PA, the body’s natural clot-busting compound, was “markedly blunted.”
That combination is concerning because narrowed vessels and slower clot clearance are part of how ischemic strokes happen. The authors stressed an important limit: this was a laboratory study on cells, not people, and more advanced testing will be needed to confirm the effects.
Should You Stop Using It?
Not necessarily, but it is worth knowing where it hides.
None of these studies prove that a sugar-free soda will cause a heart attack or stroke. Observational studies can show links, not cause and effect, and lab results do not always translate to the human body. Erythritol remains widely sold in the United States, where it is generally recognized as safe for use in foods.
Still, the findings line up with broader advice. In 2023, the World Health Organization recommended against relying on non-sugar sweeteners for weight control. People with diabetes or heart disease, who are the heaviest users of these products and were the group with the clearest link in the 2023 study, may want to talk with their doctor. Reading labels helps: erythritol often appears in drinks, “keto” desserts, protein bars and chewing gum.
The sweetener that seemed like a free pass may turn out to be more complicated. For now, the most cautious reading of the research is the simplest one: sugar-free is not the same as effect-free.
