Erythritol, a sugar alcohol used in many “keto-friendly” and “sugar-free” products, has come under serious scrutiny since 2023 research linked high blood levels of it to increased risk of heart attack, stroke, and blood clots. For years it was considered one of the safest sugar substitutes available, with zero calories, no effect on blood sugar, and minimal digestive side effects. That reputation is now complicated.
The Heart Disease Connection
A 2023 study published in Nature Medicine found that people with the highest circulating levels of erythritol in their blood had roughly double the risk of a major cardiovascular event (heart attack, stroke, or death) compared to those with the lowest levels. The research involved over 4,000 patients across separate U.S. and European cohorts who were already undergoing cardiac evaluation, and the association held up even after adjusting for traditional risk factors like age, diabetes, and blood pressure.
This was an observational study, meaning it showed a correlation, not proof that erythritol directly caused heart problems. But what came next moved the concern beyond correlation. The same research team ran lab and animal experiments showing that erythritol made blood platelets more reactive, essentially priming them to clump together and form clots more readily.
Erythritol Makes Blood Clot More Easily
A follow-up study in healthy volunteers confirmed this clotting concern in humans. After drinking a beverage containing 30 grams of erythritol (a quantity you could easily get from a couple of keto snack bars or drinks), participants experienced a more than 1,000-fold increase in erythritol plasma concentration. Their platelets became significantly more reactive across every measure tested, releasing higher levels of chemical signals that promote clot formation.
A control group that drank 30 grams of regular glucose showed none of these effects. The distinction matters because it rules out a general response to consuming something sweet. Erythritol specifically enhanced the blood’s tendency to clot. For someone already at risk for cardiovascular disease, with narrowed arteries or other underlying conditions, that heightened clotting potential could be dangerous.
How Erythritol Moves Through Your Body
Unlike most sugar alcohols, erythritol is absorbed into the bloodstream rather than passing straight through to the gut. After a single dose, blood levels peak around 90 minutes and remain elevated for hours. About 78% of what you consume is eventually excreted unchanged through urine over 24 hours, with the kidneys doing most of the work. The body doesn’t meaningfully break it down or metabolize it for energy.
This matters because erythritol lingers in your blood at high concentrations for a meaningful window of time. Your body also produces tiny amounts of erythritol naturally as a byproduct of glucose metabolism, but those background levels are vanishingly small compared to what you’d get from eating a product sweetened with it. The 1,000-fold spike seen in the platelet study illustrates just how dramatically dietary erythritol overwhelms those natural baseline levels.
Blood Sugar and Insulin Effects
One area where erythritol still looks favorable is blood sugar control. It has a glycemic index of 0, meaning it causes no measurable rise in blood glucose. Its insulin index is 2 (compared to 100 for glucose), so it triggers essentially no insulin response either. This is why it became so popular among people managing diabetes or following low-carb diets.
However, a recent randomized controlled trial comparing erythritol to xylitol (another sugar alcohol) in obese individuals found that erythritol was not effective at improving glycemic control markers like fructosamine, a measure of average blood sugar over two to three weeks. Xylitol showed more promise on that front. The study also found that erythritol consumption was associated with shifts in gut bacteria that correlated with worse glycemic outcomes, though this research is preliminary.
Digestive Side Effects
Erythritol has long been marketed as gentler on the stomach than other sugar alcohols like sorbitol or maltitol, and that’s generally true. Because most of it gets absorbed in the small intestine rather than fermenting in the colon, it causes less gas and bloating at typical doses. But it’s not side-effect-free. The laxative threshold is estimated at about 0.66 grams per kilogram of body weight for men and 0.8 grams per kilogram for women. For a 150-pound man, that works out to roughly 45 grams, an amount that’s reachable if you’re consuming multiple erythritol-sweetened products in a day.
Regulatory Status Hasn’t Changed
Despite the cardiovascular findings, erythritol remains classified as “Generally Recognized as Safe” (GRAS) by the FDA. The agency reviewed a notification from Cargill in 2019 and stated it had “no questions” about erythritol’s use across a wide range of food categories at concentrations up to 99%. No safety warnings or label changes have been issued since the 2023 research was published.
The World Health Organization, separately, released a 2023 guideline advising against using non-sugar sweeteners for weight control, citing a lack of long-term benefit for reducing body fat and potential links to other health risks. That guideline covers the broader category of sugar substitutes rather than singling out erythritol specifically.
What to Use Instead
If the erythritol research concerns you, the picture with alternatives is mixed. Xylitol, another popular sugar alcohol, has drawn similar cardiovascular concerns from the same research group. Stevia and monk fruit haven’t been linked to the same clotting risks, but there’s an important catch: many stevia and monk fruit products sold in packets or granulated form use erythritol as a bulking agent. If you’re trying to avoid erythritol, check the ingredients list. Liquid stevia drops are one way to get sweetness without sugar alcohols.
Stanley Hazen, the Cleveland Clinic cardiologist who led the erythritol research, has suggested that small amounts of real sugar, honey, or maple syrup may actually be a healthier choice than sugar alcohols for people who can tolerate them. That’s a notable shift from the long-standing assumption that zero-calorie sweeteners are automatically the safer option. The key word is moderate: nobody is suggesting you replace erythritol with large quantities of sugar, but a teaspoon of honey in your tea carries none of the platelet concerns that have emerged around erythritol.