Study Links Common Sweetener to Stroke, Blood Clot Risk

Researchers find erythritol, found in protein bars and zero-sugar drinks, may affect blood vessel function and clotting.

Mar. 30, 2026 at 8:05pm

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An extreme close-up X-ray photograph of a human brain blood vessel, revealing its intricate internal structure in a ghostly, translucent style that conceptually illustrates the potential effects of erythritol on vascular health.An X-ray view into the delicate workings of the brain's blood vessels, where exposure to a common sweetener may disrupt normal function.Boulder Today

Researchers at the University of Colorado Boulder have found that erythritol, a common sugar alcohol used as a sweetener in protein bars, zero-sugar drinks, and other foods, may increase the risk of stroke and blood clots. Their study showed that exposure to erythritol led to changes in human brain blood vessel cells, including reduced production of nitric oxide to relax blood vessels and increased production of a compound that constricts them. The researchers also found the erythritol blunted the cells' ability to break down blood clots.

Why it matters

This research builds on a previous epidemiological study that linked higher blood levels of erythritol to an elevated risk of heart attack and stroke. If confirmed in further clinical trials, the findings could prompt a re-evaluation of the widespread use of erythritol as a sugar substitute in many popular health foods and beverages.

The details

The CU Boulder researchers cultured human brain blood vessel cells and exposed them to an amount of erythritol equivalent to a single serving of a zero-sugar drink. They found this led to a 75% increase in free radical compounds, a 25% decrease in the cells' production of a compound that breaks down blood clots, and changes that constrict blood vessels. The researchers say these effects could raise stroke risk, though more research is needed to determine causality.

  • The CU Boulder study was published in the Journal of Applied Physiology in 2026.

The players

Christopher DeSouza

The director of CU Boulder's Integrative Vascular Biology Lab and a co-author of the study.

Auburn Berry

A graduate researcher in DeSouza's lab and a co-author of the study.

George Dan Mogoşanu

An associate professor at the University of Medicine and Pharmacy of Craiova in Romania who co-published a letter in the same journal emphasizing the need for more research on the dual origins of erythritol in the body.

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What they’re saying

“Given the epidemiological study that inspired our work, and now our cellular findings, we believe it would be prudent for people to monitor their consumption of non-nutrient-sweeteners such as this one.”

— Christopher DeSouza, Director, CU Boulder Integrative Vascular Biology Lab

“If your [blood] vessels are more constricted and your ability to break down blood clots is lowered, your risk of stroke goes up.”

— Auburn Berry, Graduate Researcher, CU Boulder

“Without addressing this dual origin, causality between dietary erythritol and vascular risk remains speculative.”

— George Dan Mogoşanu, Associate Professor, University of Medicine and Pharmacy of Craiova

What’s next

The researchers say deeper clinical research would be needed to fully understand the potential risks of erythritol consumption. They note that someone who regularly consumes multiple servings of erythritol-containing products could experience more extreme effects than what was observed in their study.

The takeaway

This study raises concerns about the widespread use of erythritol as a sugar substitute in many popular health foods and beverages, as it suggests the compound may negatively impact blood vessel function and clotting in ways that could increase stroke risk. However, more research is still needed to establish a clear causal link.