Xylitol and Cardiovascular Risk: What the ESC Study Revealed

A few days ago, I reached for some xylitol gum at a convenience store but froze at the counter. A news alert on my phone had caught my eye, with the headline: “Xylitol increases heart attack risk by 57%.”

Isn’t this the gum my dentist recommends every time I go for a check-up? I’ve been chewing it for years without a second thought because it’s supposed to be good for preventing cavities, so hearing about cardiovascular disease suddenly felt jarring.

I ended up putting the gum back, went home, and looked up the original study and related reports.

Xylitol and Cardiovascular Risk: What Was Announced at the ESC?

At the European Society of Cardiology (ESC) Annual Congress held in Munich, Germany, from August 28 to 31, 2026, a research team led by Dr. Marco Witkowski from Charité – Universitätsmedizin Berlin presented findings on August 29 regarding the link between blood xylitol levels and the incidence of cardiovascular disease.

The study involved a total of 17,710 participants from the Canadian Longitudinal Study on Aging (CLSA) and the UK’s EPIC-Norfolk cohort. Both are large-scale prospective cohorts originally launched for other purposes. The researchers measured xylitol levels in stored blood samples, divided participants into four groups, and tracked the incidence of Major Adverse Cardiovascular Events (MACE)—a composite of heart attack, stroke, and death.

The results followed the same pattern in both cohorts.

In the Canadian group, those in the top 25% for blood xylitol levels had a 57% higher risk of experiencing a MACE within 6 years compared to those in the bottom 25%.

The UK cohort, which had a much longer follow-up period of 30 years, showed an 18% increase in risk. This difference reportedly persisted even after statistically adjusting for traditional risk factors such as age, sex, smoking, hypertension, diabetes, and lipid levels.

While the absolute figures differ between the two cohorts (comparing 6 years vs. 30 years is inherently difficult), the research team emphasizes that the finding was consistently replicated in the same direction.

Just How Ubiquitous Is Xylitol?

Before worrying about xylitol side effects, we need to address a fact: this ingredient is far more widespread than you might think.

Xylitol is a sugar alcohol sweetener that has fewer calories than sugar, raises blood sugar less, and maintains almost the same level of sweetness. Because it’s known to prevent cavities—as oral bacteria responsible for decay cannot easily break it down—it is treated as a staple ingredient in sugar-free gum, candy, toothpaste, and mouthwash.

It doesn’t stop there.

Diet drinks, low-sugar snacks, baked goods, ice cream, and even chewable vitamins and cough syrups use xylitol as a sweetener. Looking into pharmaceutical industry reports, I found it’s also used as a binder and filler for pill coatings and chewable tablets.

In other words, it’s not just in the “products you intentionally chose to avoid sugar”; it’s hidden in many items we consume without a second thought. I was surprised to learn how common it is in children’s candy and chewable vitamins.

Digging deeper into the ESC presentation materials, I found an interesting statistic.

The human body naturally produces a very small amount of xylitol during glucose metabolism. However, the amount of xylitol artificially added to foods is often over 1,000 times higher than this natural production. This means that the argument “xylitol is naturally occurring in the body, so it’s fine” might be missing the point, as the concentration we actually ingest is on a completely different scale. It is difficult to judge the safety of a substance present in trace amounts naturally versus one added in high concentrations during manufacturing.

How Were Xylitol Safety Standards Originally Set?

There is a history behind why xylitol became so widely used.

It is a substance extracted from xylose, a sugar found in small amounts in plant fibers like birch trees or corn cobs. Its rise to prominence actually dates back to the wartime conditions in Finland in the 1940s.

With sugar imports blocked by naval blockades during the Winter War and the Continuation War against the Soviet Union, Finnish researchers began studying xylitol—extractable from the country’s abundant birch resources—as a sugar substitute. However, the process was too complex and expensive at the time, and it was forgotten for a while once sugar supplies normalized after the war. It wasn’t until the 1970s, when its cavity-preventing effects were scientifically confirmed, that it was commercialized in the gum and toothpaste market.

Therefore, xylitol’s reputation for being “safe” was built from the start with the narrow goal of cavity prevention in mind.

South Korea’s Ministry of Food and Drug Safety sets a daily intake guideline of 10–25g for xylitol’s cavity-prevention function, and general guides usually recommend 5–30g per day for adults. Exceeding this range has historically been associated with typical sugar alcohol side effects, such as diarrhea or bloating due to poor intestinal absorption. (Note: It is toxic to dogs, causing rapid insulin release and hypoglycemia, so it must be treated entirely differently from human standards.) In other words, current safety standards were set from a “gut health” perspective and have never been re-evaluated from a “vascular and blood clot” perspective. Since the possibility of cardiovascular side effects wasn’t even on the research list when these standards were created, it’s more accurate to say that these standards were “answers to a different question” rather than saying they are wrong.

Perhaps this is why the ESC study is being received as controversial—it is applying an entirely new set of criteria to a substance that was considered safe by old standards.

Is There Evidence for the Mechanism of Xylitol-Induced Blood Clots?

Looking only at the numbers, one might dismiss this as mere correlation. However, the research team offered an explanation for why vessels might become blocked.

In the same presentation, they shared results from a small experiment with 10 healthy adults, observing indicators of increased platelet reactivity after consuming a xylitol-containing drink. Platelets are cells that normally clump together to help stop bleeding when an injury occurs. If they become prone to clumping more than necessary, they can easily cause unwanted blood clots within vessels. Since many heart attacks and strokes occur when these clots completely block a vessel, the explanation that “xylitol promotes clotting” provides a plausible mechanism for the epidemiological correlation mentioned earlier.

Personally, the term “increased platelet reactivity” felt vague at first, but it essentially means this: if platelets become stickier and more prone to clumping, even minor damage to the vessel wall can easily lead to the formation of an excessively large clot. It’s a mechanism that is hard to ignore, as it suggests that minor vascular damage that would normally be harmless could turn into a life-threatening blockage when platelets are in a hypersensitive state.

In fact, this announcement is not entirely new. The same research team published a paper in the European Heart Journal (EHJ) in 2024 with similar conclusions.

They observed 1,157 patients with a history of cardiovascular disease and found that those with higher blood xylitol levels experienced more cardiovascular events over the next 3 years; this result was replicated in a separate cohort of 2,149 people. This ESC presentation is a follow-up that expands the scope to include “general individuals without a history of cardiovascular disease.” The key expansion here is that the same pattern emerged in healthy populations, not just those already suffering from illness.

Why Does This Team Keep Targeting This Class of Ingredients?

There is one point I want to dig into further. Dr. Witkowski’s research team originally comes from Dr. Stanley Hazen’s lab at the Cleveland Clinic. And xylitol isn’t the first ingredient this group has scrutinized.

In a 2023 paper published in Nature Medicine, researchers from the same lineage covered another sugar alcohol, erythritol. They analyzed plasma samples from 4,000 patients at risk for cardiovascular disease and found that those with higher erythritol levels were about twice as likely to experience a cardiovascular event within 3 years. The following year, in 2024, they conducted an intervention study where healthy volunteers drank an erythritol beverage; while there was no change in platelet activity with sugar, it rose significantly with erythritol.

When you look at this progression, the picture becomes clearer: Correlation confirmed with erythritol (2023) → Platelet response confirmed after actual consumption of erythritol (2024) → Correlation confirmed with xylitol in patients with cardiovascular disease (2024, EHJ) → Large cohort confirmation of xylitol in the general population (2026, ESC). The same research group has been repeatedly verifying a single hypothesis across multiple ingredients and groups: that “sugar alcohol sweeteners act to stimulate platelets and promote blood clots.”

Perhaps the cumulative direction of this research is more noteworthy than any single announcement. It would be difficult to repeatedly get similar results by switching ingredients if it were just a one-time accidental correlation.

Does This Prove Causality?

However, we must note that this announcement is a conference presentation, not a study that has gone through formal peer review and been published in a journal. Furthermore, this was an observational study, which shows a correlation between xylitol levels and cardiovascular events, but it is not designed to prove the causal link that “eating xylitol caused the disease.”

Professor Dan Atar of the ESC Communications Committee also drew a line in his commentary on the presentation, stating, “As it is an observational study, it is difficult to infer causality,” while adding that it is clearly a topic requiring further research.

In fact, when the 2024 EHJ paper was released, a rebuttal comment was published in the same journal. Other researchers, such as Bonomini et al., pointed out the possibility of reverse causality—that people with high xylitol levels might have had underlying metabolic disease or impaired kidney function that prevented them from processing xylitol properly. In other words, the disease might not have been caused by eating xylitol; rather, xylitol levels might have naturally been higher in the bodies of people who were already metabolically unhealthy. This remains an unresolved question.

How Is This Different from Other Sweeteners Like Stevia or Allulose?

Reading this, one might suspect all alternative sweeteners, but this study specifically targets the narrow category of “sugar alcohols.” This includes xylitol, erythritol, sorbitol, and mannitol—ingredients ending in “-itol.” They share a chemical structure similar to sugar, meaning their absorption pathways in the gut overlap to some extent. In contrast, sweeteners like stevia, allulose, and monk fruit are chemically entirely different and have not been reported to cause the same platelet reactivity issues in studies to date. Of course, “not reported” doesn’t mean “proven safe forever”; it just means there haven’t been large-scale studies examining them in this way yet.

However, this distinction is practically useful for consumers. If you see names like “xylitol,” “erythritol,” or “sorbitol” on an ingredient label, it falls under the category currently being discussed. If you see “stevia extract,” “allulose,” or “sucralose,” they are chemically distinct. It’s one more reason to take a closer look at the labels when choosing diet drinks or sugar-free products.

What Needs to Happen to Resolve This Debate?

The answer depends on how future studies are designed, as the debate between observational studies and reverse causality remains intense.

The current evidence is divided into two paths:

One is the cohort study that simply observed the correlation between blood xylitol levels and cardiovascular events in humans.

The other is a small-scale intervention study that had healthy volunteers drink xylitol beverages and observed platelet response.

The latter provides evidence closer to causality by showing that “consumption changed the reaction,” but with a sample size of only 10, it did not confirm actual hard clinical endpoints like heart attacks or strokes.

The research team seems aware of this, repeatedly using the phrase “further research is needed” in their comments. The most definitive way for the academic community to settle this debate is through a Randomized Controlled Trial (RCT). This would involve randomly assigning groups to consume xylitol over a long period versus a control group and tracking them for years to compare cardiovascular event rates. Such large-scale, long-term RCTs are expensive and complex to design, so they won’t yield immediate results. Until then, we have no choice but to observe how the body of observational research grows and how the research into platelet and clotting mechanisms becomes more refined.

Should You Stop Eating Xylitol Right Now?

To conclude, even the research team does not recommend “avoiding xylitol entirely right now.” Instead, they emphasize that “the amount of xylitol added to products is constantly increasing, yet we know very little about the long-term safety of this ingredient.”

Xylitol is still classified as Generally Recognized as Safe (GRAS) by the U.S. FDA and remains an approved food additive in Europe. Regulatory authorities have not taken any action.

Personally, I was confused about whether this means eating a ton of sugar instead is a better choice, but reports suggest that is not the conclusion either. Cardiovascular risk is ultimately driven far more by overall lifestyle factors like smoking, blood pressure, blood sugar, weight, and activity level. It is probably more realistic to look at how often and how much you consume within your overall diet rather than reacting extremely to one specific sweetener.

However, if you already have cardiovascular disease or are at high risk for blood clots due to diabetes or metabolic syndrome, the situation might be different. Given that both the current ESC study and the 2024 EHJ study consistently showed clearer signals in “groups with underlying conditions,” it would be safer to discuss the frequency of xylitol-containing product consumption with your doctor. Conversely, for those without specific cardiovascular risk factors, there is currently insufficient evidence to fear consuming it within the recommended daily intake range (around 5–30g). The researchers themselves are advocating for “long-term RCTs” rather than suggesting an “immediate recall.”

In my case, I plan to continue chewing gum, but I’ll cut back on the habit of chewing several packs a day. Since there is no definitive answer yet, I’ll wait for the next paper or follow-up conference announcement before making any further changes.