Xylitol and Cardiovascular Risk: Findings from the ESC Study
A few days ago, I reached for a pack of xylitol gum at the convenience store but paused at the checkout counter. It was because of a news notification on my phone with the headline: “Xylitol increases heart attack risk by 57%.”
Wait, isn’t this the gum my dentist has been recommending for years? I’ve been chewing it without a second thought for the sake of cavity prevention, so hearing about cardiovascular disease suddenly left me confused.
Ultimately, I put the gum back, went home, and spent time reading the original research and related reports.
What did the ESC report regarding xylitol and cardiovascular risk?
From August 28 to 31, 2026, at the European Society of Cardiology (ESC) annual congress in Munich, Germany, Dr. Marco Witkowski’s research team from Charité – Universitätsmedizin Berlin presented findings on the correlation between blood xylitol levels and cardiovascular disease (CVD) on August 29.
The study involved 17,710 participants from the Canadian Longitudinal Study on Aging (CLSA) and the UK’s EPIC-Norfolk cohort. Both are large, prospective cohorts originally established for other purposes. The researchers measured xylitol concentrations in stored blood samples, divided participants into four groups, and tracked the incidence of Major Adverse Cardiovascular Events (MACE), which includes heart attack, stroke, and death.
The results were consistent across both cohorts.
In the Canadian cohort, those in the top 25% of blood xylitol levels had a 57% higher risk of experiencing MACE within six years compared to the bottom 25%.
For the UK cohort, the tracking period was much longer, covering 30 years of data, where the increased risk was 18%. This difference remained statistically significant even after 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 to 30 years is inherently difficult), the research team emphasizes that the trend was consistently observed in both.
Where exactly is xylitol found?
Before worrying about potential side effects, it is important to realize how ubiquitous this ingredient is.
Xylitol is a sugar alcohol sweetener that provides the same sweetness as sugar with fewer calories and less impact on blood glucose. Since it is widely known that oral cavity bacteria cannot easily ferment xylitol—leading to cavity prevention—it has become a staple ingredient not just in sugar-free gum and candy, but also in toothpaste and mouthwash.
But 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 reports from the pharmaceutical industry, I found it is also used as a binder or filler for tablet coatings and chewable medications.
In other words, it’s not just in “products you chose specifically to avoid sugar”; it is already hidden behind the labels of many items we consume without a second thought. I was surprised to learn how common it is in children’s candy and chewable vitamins.
Looking deeper into the ESC presentation, an interesting figure emerges.
While the human body naturally produces a tiny amount of xylitol during glucose metabolism, the amount of xylitol artificially added to food often exceeds this natural production by more than 1,000 times. This suggests that the logic that “xylitol is fine because it’s a substance naturally present in the body” may be comparing apples and oranges, given the vast difference in concentrations. It is difficult to treat a substance that exists in trace amounts naturally the same as one added in high concentrations during manufacturing.
How were xylitol safety standards originally established?
Xylitol’s widespread use has a unique history.
It is derived from xylose, a sugar found in small quantities in plant fibers like birch trees or corn cobs. Its initial spotlight, unexpectedly, came from the wartime conditions in Finland in the 1940s.
With sugar imports blocked by naval blockades during the Winter and Continuation Wars with the Soviet Union, Finnish researchers began studying xylitol, which could be extracted from the country’s abundant birch resources, as a sugar substitute. However, the process was initially too complex and expensive, and as sugar supply normalized after the war, it was forgotten for a time. It wasn’t until the 1970s, when its cavity-preventing effects were scientifically confirmed, that it was commercialized in the gum and toothpaste markets.
Therefore, xylitol’s reputation for being “safe” was built from the start on the narrow objective of cavity prevention.
South Korea’s Ministry of Food and Drug Safety sets a daily intake guideline of 10–25g for cavity prevention, and commercial sources generally suggest a daily intake of 5–30g for adults. Beyond this range, the typical side effects of sugar alcohols, such as diarrhea or bloating due to poor intestinal absorption, were the primary concerns known until now. (Note: For dogs, even small amounts can trigger a rapid insulin release, causing hypoglycemia, so it must be treated entirely differently.) In other words, previous safety standards were established from the perspective of “gut health”, not from the perspective of “blood vessels and blood clots” as they are being re-examined now. Since the possibility of cardiovascular side effects wasn’t even on the list of studies when these criteria were set, it is more accurate to say that “they were answers to different questions” rather than saying the criteria were wrong.
Perhaps this is why the ESC study is considered controversial—they are applying an entirely new set of criteria to a substance that was considered safe under old ones.
Is there a mechanism for how xylitol causes blood clots?
Looking only at the numbers, one might dismiss this as a mere correlation, but the research team also provided an explanation for why blood vessels might become blocked.
In the same presentation, results from a small-scale experiment involving 10 healthy adults were revealed, showing that markers for increased platelet reactivity were observed after consuming xylitol-containing beverages. Platelets are cells that normally clump together to help blood clot when an injury occurs; however, when they become prone to clumping more than necessary, it becomes easier for unnecessary blood clots to form within blood vessels. Since many heart attacks and strokes occur when these clots completely block a vessel, the explanation that “xylitol acts in a way that promotes blood clot formation” adds a plausible mechanism to the epidemiological correlation mentioned earlier.
Personally, the term “increased platelet reactivity” felt vague at first, but it essentially means this:
When platelets become more “sticky” to each other, even minor damage to the vessel wall can easily lead to the formation of an excessively large clump (blood clot). I realized that this is a mechanism that cannot be entirely ignored, as minor vessel damage that would normally resolve without issue could lead to a vessel-blocking event 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 that reached similar conclusions.
They observed 1,157 patients with a history of cardiovascular disease, finding that those with higher blood xylitol levels experienced more cardiovascular events over the next three years, a result replicated in a separate cohort of 2,149 people. This ESC presentation is essentially a sequel that expanded the scope to “the general public without a history of cardiovascular disease.” The core expansion of this presentation is that the same pattern emerged in healthy individuals, not just those already suffering from the disease.
Why does this research team keep targeting this class of ingredients?
There is one point I want to dig into further. Dr. Witkowski’s research team comes from the lab of Dr. Stanley Hazen at the Cleveland Clinic. And xylitol is not the first substance this group has scrutinized.
In 2023, researchers from the same group published a paper in Nature Medicine dealing with another sugar alcohol, erythritol. Analyzing plasma samples from about 4,000 patients at risk for cardiovascular disease, they found that those with higher erythritol levels were about twice as likely to experience a cardiovascular event within three years. The following year, in 2024, they conducted an intervention study where healthy volunteers consumed erythritol beverages and observed platelet reactions; while there were no changes when sugar was consumed, platelet activity increased significantly with erythritol.
When you line up this sequence, the picture becomes clearer: Correlation confirmed with erythritol (2023) → Platelet reaction confirmed after actual ingestion of erythritol (2024) → Correlation confirmed with xylitol in cardiovascular patients (2024, EHJ) → Large-scale cohort confirmation for xylitol in the general public (2026, ESC). The same research group has been repeatedly validating a single hypothesis across multiple ingredients and groups: that sugar alcohol-based sweeteners act to stimulate platelets and promote blood clots.
Rather than looking at individual announcements, this cumulative direction is perhaps more noteworthy. It would be difficult for similar results to appear repeatedly while changing ingredients if it were just a one-time accidental correlation.
Even so, causality is not proven
However, one thing must be pointed out. This announcement is still at the stage of a conference presentation, not a formal peer-reviewed paper published in a journal. Furthermore, because this is an observational study, while it shows a correlation between xylitol levels and cardiovascular events, 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 subject that requires further research.
In fact, when the previous 2024 EHJ paper was released, a rebuttal commentary was published in the same journal. Other researchers, such as Bonomini, pointed out the possibility of reverse causality—that people with high xylitol levels might have had underlying metabolic diseases or impaired kidney function that prevented their bodies from processing xylitol, meaning the disease could be the cause of the high levels, not the result. In other words, it is possible that xylitol levels appeared naturally high in people who already had poor metabolic health. This part seems to remain unresolved.
How is this different from other sweeteners like Stevia or Allulose?
Reading this far, one might be tempted to suspect all alternative sweeteners, but this study specifically targets the narrow class of “sugar alcohols.” This includes ingredients ending in “-itol” like xylitol, erythritol, sorbitol, and mannitol, which share a chemical structure similar to sugar and follow similar absorption pathways in the gut. On the other hand, sweeteners like stevia, allulose, and monk fruit belong to entirely different chemical classes, and no such platelet reactivity issues have been reported in studies to date. Of course, the fact that “nothing has been reported” does not mean they are “safe forever,” but rather that there haven’t been large-scale studies examining this class yet.
However, this distinction is practically meaningful for consumers. If you see names like “xylitol,” “erythritol,” or “sorbitol” on the ingredient list, they belong to the class under discussion. If you see names like “stevia extract,” “allulose,” or “sucralose,” you can consider them chemically distinct ingredients. It just means there’s one more reason to check the ingredient label when choosing diet drinks or sugar-free products.
What more is needed to settle this debate?
With observational studies and reverse-causality debates clashing so intensely, the answer ultimately depends on how the next stage of research is designed.
The evidence so far comes in two main branches:
One is cohort studies that simply observe the correlation between blood xylitol levels and cardiovascular events in humans,
The other is small-scale intervention studies where healthy volunteers consume xylitol beverages and researchers observe platelet reactions.
The latter provides evidence closer to causality because it shows a “reaction changed after consumption,” but the sample size is only around 10 people, so it has not confirmed actual clinical outcomes (hard 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 either consume xylitol long-term or not, and tracking them for several years to directly compare the incidence of cardiovascular events. However, such large-scale, long-term RCTs are expensive and complex to design, so they are not the type of research that yields immediate results. Until then, we have no choice but to watch how the body of observational studies grows and how much more precise the research on platelet and blood clot mechanisms becomes.
Should I stop eating xylitol right now?
To give you the conclusion first, even the research team does not recommend “avoiding xylitol completely right now.” Instead, they emphasize that “the amount of xylitol added to products is constantly increasing, but 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 maintains its status as an approved food additive in Europe. In other words, no regulatory action has been taken by authorities.
Personally, I was confused about whether eating tons of sugar instead of xylitol would be a better choice, but related reports suggest that is not the conclusion either.
Cardiovascular risk is ultimately driven much more by overall lifestyle factors like smoking, blood pressure, blood glucose, weight, and activity levels. It is more realistic to look at how often and how much you consume within your overall diet rather than reacting extremely to a single sweetener.
However, if you already suffer from cardiovascular disease or have a high risk of blood clots due to diabetes or metabolic syndrome, the situation might be different.
Given that both this ESC study and the 2024 EHJ study consistently showed more pronounced signals in “groups with underlying conditions,” it would be safer to discuss the frequency of consuming xylitol-containing products with your doctor. Conversely, for someone with no particular cardiovascular risk factors, there is currently insufficient evidence to fear eating it within the recommended daily intake range (around 5–30g). The research team itself is of the position that “long-term randomized controlled trials are needed,” not that “it should be recalled immediately.”
In my case, I plan to keep chewing gum but will reduce my habit of chewing several packs a day. Since there is no definitive answer yet, I intend to wait and see until the next paper or follow-up conference presentation comes out.