Could the Sweetener Erythritol Be Undermining Your Brain’s Protective Barrier?

The sugar‑alcohol sweetener erythritol has long been regarded as a safe substitute for sugar, widely used in products ranging from “sugar‑free” bars to keto‑friendly drinks. But a new laboratory study suggests that erythritol may quietly interfere with one of the body’s most important protection systems: the blood‑brain barrier (BBB). The implications, researchers say, could extend to increased risk of stroke and other cardiovascular issues.

What the study found

A team at the University of Colorado exposed human‑cell models of the blood‑brain barrier to concentrations of erythritol typical of those found after drinking a soft drink. They observed that erythritol triggered a series of harmful cellular events:

The cells experienced oxidative stress — an overload of reactive molecules and a reduction in antioxidant defences.

The barrier‑cells’ ability to regulate vessel dilation and blood flow was disrupted. Specifically, erythritol lowered production of nitric oxide (which relaxes blood vessels) and increased endothelin‑1 (which constricts them).

The molecules normally released to dissolve blood clots (for example, tissue plasminogen activator) were inhibited, potentially leaving clots free to block blood flow.

These disruptions are meaningful because they mirror key biological pathways involved in ischemic strokes — where blocked blood vessels starve brain tissue of oxygen and nutrients.
Why this matters

The BBB is the brain’s security gate. It allows essential nutrients in, and keeps toxins and harmful agents out. If its function is compromised, the brain becomes more vulnerable to damage. The study’s suggestion that a commonly used sweetener might interfere with this barrier raises important questions.

In addition, human observational studies have linked higher blood levels of erythritol with significantly elevated risks of cardiovascular events. One large cohort found people with the highest erythritol levels were roughly twice as likely to suffer major cardiac incidents.

Limitations & context

While the results are concerning, it’s critical to interpret them carefully:

The study was conducted on isolated cells in laboratory dishes, not in human subjects or intact blood‑vessel systems. Real physiological responses may differ.

The authors themselves call for more advanced models (e.g., “blood vessel on a chip”) and in‑vivo studies to verify whether the effects occur in living humans.

Regulatory agencies such as the U.S. Food & Drug Administration (FDA) and the European Food Safety Authority (EFSA) have approved erythritol as safe for consumption under current guidelines.

So while this research adds an important new perspective, it does not yet constitute conclusive proof of direct harm in everyday human consumption.

What consumers should consider

Given the emerging evidence, here are some practical considerations:

If you often consume products labelled “sugar‑free,” “keto‑friendly,” or “zero‑calorie sweetened” that rely on erythritol, it may be wise to moderate intake and not assume they are risk‑free.

Water, natural whole‑foods, and limiting ultra‑processed sweetened items remain strong nutritional practices.

If you have existing cardiovascular risk factors (such as obesity, diabetes, high blood pressure) you may wish to discuss with your healthcare provider whether you should monitor your use of sweeteners like erythritol.

Stay tuned for further human‑based research: these findings may influence future dietary guidelines or sweetener approvals.

Conclusion