A new study involving nearly 18,000 people, presented at the 2026 congress of the European Society of Cardiology, suggests that xylitol — a sugar substitute often used in chewing gum and other low-calorie products — may be linked to a higher risk of serious health events such as heart attacks, strokes, or death. The research, led by Marco Witkowski from the Charité University Hospital in Berlin, examined data from two large studies: the Canadian Longitudinal Study on Aging and the British EPIC-Norfolk study. In the Canadian group, which was followed for six years, people with the highest levels of xylitol in their blood had a 57% greater risk of experiencing major cardiovascular events compared to those with the lowest levels. In the British group, followed for thirty years, the risk was 18% higher. These associations remained even after researchers accounted for factors like age, sex, smoking, weight, diabetes, high blood pressure, and cholesterol levels. Xylitol is a type of sugar alcohol, or polyol, that has a sweetness similar to regular sugar but with fewer calories. It is widely used in sugar-free products such as gum, candies, and beverages, and it occurs naturally in small amounts in fruits and vegetables. It is also produced in tiny amounts by the human body. The study found that the relationship between xylitol and cardiovascular events was gradual — the higher the levels of xylitol in the blood, the more likely individuals were to experience heart attacks, strokes, or die during the study period. This research builds on a 2024 study published in the European Heart Journal, which found a link between high xylitol levels and increased cardiovascular risk in people already at higher risk for heart disease. Earlier experiments had suggested that xylitol might make blood platelets more reactive, potentially increasing the chance of blood clots. However, the new study is observational, meaning it shows a correlation but does not prove that xylitol directly causes heart attacks or strokes. The researchers measured blood xylitol levels rather than the amount participants actually consumed. High xylitol levels could also be due to individual differences in how the body processes or produces the substance. Witkowski emphasized that the findings highlight a lack of understanding about the cardiovascular safety of xylitol. He noted that more research is needed to determine how much of the potential risk is actually due to xylitol consumption and at what levels. Until then, he suggested a balanced approach — using xylitol in moderation and not replacing it with excessive amounts of regular sugar, which also carries health risks.