The Sweetener That May Harm Your Brain

Sugar-free labels promise guilt-free indulgence. But when it comes to your brain health, one popular sweetener may be doing more harm than good.

You’ve probably seen erythritol listed on the back of your favorite “diet” drinks or sugar-free snacks. Marketed as a natural, safe alternative to sugar—especially for those watching their blood sugar—it’s become a go-to additive in low-calorie products.

But new research out of the University of Colorado Boulder may force us to rethink that “safe” label.

In a recent laboratory study, scientists exposed human brain blood vessel cells to erythritol—at levels equivalent to drinking just one artificially sweetened beverage. Within hours, they observed multiple signs of cellular distress, including:

• A 75% increase in oxidative stress, which damages cells over time
• A drop in nitric oxide production, a molecule that helps keep blood vessels open and healthy
• A 30% rise in endothelin-1, which causes blood vessels to constrict
• A complete shutdown of the brain’s natural clot-dissolving response

In plain English? Erythritol may be impairing the very cells that help regulate blood flow to your brain and prevent clots—raising concerns about stroke risk, especially in people who regularly consume sugar-free products.

The lead researchers didn’t mince words, calling these effects “central characteristics” of the kind of vascular dysfunction linked to ischemic stroke—the most common kind of stroke caused by blood clots in the brain.

We’ve talked about artificial sweeteners before. While they’re often promoted as the “healthier” option for managing weight or diabetes, they’re not without risk.

This study adds to a growing pile of evidence suggesting that what we replace sugar with matters just as much as sugar itself.

Now, to be fair—this was a lab study, not a trial in living humans. But the researchers were careful to test realistic levels of erythritol, not some outrageous dose. Their goal? To mirror what happens in the body after just one standard “sugar-free” treat.

And it’s not the first red flag.

Earlier studies found that people with higher blood levels of erythritol had an elevated risk of heart attack and stroke over time. In one small trial, ingesting erythritol spiked blood clotting activity in healthy volunteers. That’s a dangerous combination.

So what can you do?

Here’s the good news: You don’t need to give up all sweetness. But it may be time to rethink your relationship with sugar substitutes—especially if you’re using them daily.

Here are 3 smarter ways to reduce sugar without artificial risks:

1. Use whole fruits for sweetness—like berries, bananas, or dates in smoothies or baking.
2. Retrain your taste buds—slowly reduce how much sweetener you add to drinks over time.
3. Stick to natural sweeteners in moderation—like raw honey or maple syrup—only when necessary.

The takeaway? The best path forward isn’t about trading sugar for chemicals. It’s about reducing our overall dependence on overly sweet foods.

Because when it comes to your brain, that sugar-free soda might not be so guilt-free after all.

To clearer thinking and safer sweetness,

Rachel Mace
Managing Editorial Director, e-Alert
with contributions from the research team

Sources:

StudyFinds Analysis. (2025, July 15). This Popular Zero-Calorie Sweetener Could Impair Brain Blood Vessel Cells, Study Suggests. Study Finds. https://studyfinds.org/erythritol-diet-sugar-free-soda-artificial-sweetener-damaging-your-brains-blood-vessels-stroke/