Common sugar substitute linked to brain cell damage and increased stroke risk

A widely used sugar substitute found in sugar-free products may impair brain cells and increase the risk of stroke, according to new research from the University of Colorado Boulder.

The study, published in the Journal of Applied Physiology, found that erythritol, used in everything from low-carb ice cream to keto snacks and soft drinks, negatively affects brain blood vessel cells, potentially raising the risk of cardiovascular events such as stroke.

Professor Christopher DeSouza, senior author and director of the university’s Integrative Vascular Biology Lab, said:

Our study adds to the evidence suggesting that non-nutritive sweeteners that have generally been purported to be safe, may not come without negative health consequences.”

Erythritol is a sugar alcohol often made by fermenting corn. Approved by the FDA in 2001, it is about 80 percent as sweet as sugar but has virtually no calories or impact on blood glucose, making it a go-to for people watching their weight or managing diabetes.

However, recent research, including a large Cleveland Clinic study of 4,000 participants, has raised alarms by showing that higher blood levels of erythritol significantly increase the risk of heart attacks and strokes.

To explore the mechanism behind this, DeSouza and graduate researcher Auburn Berry exposed human brain blood vessel cells to erythritol concentrations equivalent to those found in a single sugar-free drink. They found multiple damaging effects: a reduction in nitric oxide (which relaxes blood vessels), an increase in endothelin-1 (which constricts them), and diminished response to thrombin, a clot-triggering compound, resulting in less production of t-PA, a clot-busting enzyme.

The treated cells also generated higher levels of reactive oxygen species (ROS), known to damage cells and inflame tissues.

Berry explained:

Big picture, if your vessels are more constricted and your ability to break down blood clots is lowered, your risk of stroke goes up. Our research demonstrates not only that, but how erythritol has the potential to increase stroke risk.”

Earlier studies showed just 30 grams of erythritol, roughly a pint of sugar-free ice cream, could make blood platelets clump together, further increasing clot risk.

Researchers urge caution

Although the new study tested cells in a lab rather than human subjects, the researchers say the findings warrant serious public caution.

DeSouza added:

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.”

Researchers urge consumers to check product labels for erythritol or the term “sugar alcohol,” especially if they consume several servings daily. While large-scale human studies are still needed to confirm these effects, early evidence supports a cautious approach to regular use of this common sugar substitute.