Researchers examined data from more than 17,700 people in two large studies, according to HealthDay.
In one study, participants were followed for six years. In the other, they were followed for 30 years.
The researchers compared the amount of a particular sweetener in participants' blood with their risk of heart attack, stroke or death.
The researchers also took into account other factors that can affect heart health.
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These included BMI, high blood pressure, diabetes and blood lipid levels.
Important caveat
The results show an association, but they do not prove that the sweetener is the cause. This is because the research is observational, according to HealthDay.
The findings are due to be presented at the European Society of Cardiology's annual congress in Munich. They have not yet been published in a peer-reviewed scientific journal and are therefore considered preliminary.
According to HealthDay, previous studies by the research team have shown that the same sweetener may make blood platelets more likely to form blood clots.
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The sugar-free substance
The sweetener is xylitol. It is used in products including sugar-free foods and drinks, chewing gum and oral care products.
In the study with six years of follow-up, people with the highest levels of xylitol in their blood had a 57 percent higher risk of heart attack, stroke or death than those with the lowest levels.
In the 30-year study, the risk was 18 percent higher.
The researchers therefore believe that further studies are needed to investigate xylitol and its potential effects on heart health.
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This article is made and published by Ida-Marie Palm Varbæk, who may have used AI in the preparation.