Sweetener You Thought Was Safe—Think Again
You’ve seen it in diet drinks. Keto snack bars. Sugar-free gum. Maybe you’ve even used it yourself in an effort to cut calories or manage blood sugar.
We’re talking about erythritol, a popular sugar substitute we’ve covered before in e-Alert—especially as studies have emerged linking it to an increased risk of heart attack and stroke.
But now, new research reveals something even more alarming.
Just one serving of an erythritol-sweetened beverage may trigger damage at the cellular level—increasing oxidative stress, decreasing blood flow in brain arteries, and possibly setting the stage for stroke and cognitive decline.
This time, the warning comes not from long-term epidemiological tracking, but from a controlled cellular study, presented at the American Physiology Summit (APS2025) last month.
And it’s raising eyebrows.
Researchers from the University of Colorado Boulder took human brain blood vessel cells and exposed them to a solution containing the same amount of erythritol found in one can of a diet soda (about 30 grams).
The results?
After just three hours, the erythritol-exposed cells produced nearly 100% more reactive oxygen species (ROS)—unstable molecules that damage cells and tissues—compared to the untreated cells.
These cells also made less nitric oxide, a molecule essential for healthy blood vessel function and circulation. Nitric oxide helps your arteries dilate and manage blood flow, especially to the brain.
Without it? You’re looking at stiffer vessels, reduced blood flow, and a greater risk of clot formation and stroke.
“Erythritol triggers a surge in harmful molecules called reactive oxygen species, which cause cellular damage,” explained Dr. Thomas Holland, a physician-scientist at Rush University. “Of particular concern is when this damage occurs in neural tissue, potentially increasing rates of cognitive decline.”
If this sounds familiar, that’s because it lines up with earlier findings.
A 2023 study published in Nature Medicine found that people with high levels of erythritol in their blood had a much higher risk of major adverse cardiac events, including heart attack and stroke.
The researchers at the time theorized that erythritol might promote blood clotting. This new cellular evidence helps explain why—by impairing blood vessel health and increasing oxidative stress, erythritol creates the perfect storm for vascular damage.
It’s worth emphasizing: erythritol has been marketed as the “healthy” sweetener. It’s noncaloric.
It doesn’t spike blood sugar.
But the growing body of research shows those benefits may come at a steep cost—particularly for those already dealing with risk factors like diabetes, obesity, or heart disease.
This study is yet another reminder that “sugar-free” doesn’t always mean safe. We’ve covered artificial sweeteners like aspartame, sucralose, and saccharin in the past—each with its own concerns, from gut microbiome disruption to possible links with cancer or metabolic dysfunction.
Now erythritol joins that list.
So what’s the solution? According to experts like Dr. Holland and study author Auburn Berry, it’s about moderation—and smarter choices.
Berry and Holland both point to stevia and monk fruit extract as noncaloric sweeteners that currently appear safer. These natural options don’t seem to have the same negative impact on oxidative stress or nitric oxide production.
Another alternative: fruit-based sweeteners, like date syrup, which may offer antioxidants. But remember, these still affect blood sugar and should be used sparingly.
And for those looking for the healthiest option of all? Start cutting back on sweeteners altogether.
“Reducing overall reliance on sweeteners and focusing on whole foods is likely the most effective path for long-term brain and vascular health,” said Dr. Holland.
We’ve long encouraged you to read labels carefully, especially when it comes to “sugar-free” or “keto-friendly” products. Erythritol may be natural and calorie-free, but that doesn’t mean it’s safe.
This new research provides more evidence that erythritol may impair blood vessel function—even in small amounts—and could contribute to serious conditions like stroke and cognitive decline.
You don’t need to avoid all sweeteners forever, but you should be mindful of how much—and what kind—you’re consuming.
Sometimes, the best health choice isn’t about swapping ingredients… it’s about going back to basics.
To curbing back your sweet tooth,
Rachel Mace
Managing Editorial Director, e-Alert
with contributions from the research team
