Common sugar substitute linked to increased risk of heart attack and stroke

Common sugar substitute linked to increased risk of heart attack and stroke

 

Xylitol, a type of sugar alcohol present in small quantities in fruits and vegetables, is commonly used in sugar-free gum, toothpaste, and baked goods.

The safety of sugar substitutes is once again under scrutiny.

Researchers from the Cleveland Clinic have linked the low-calorie sugar substitute xylitol to an increased risk of heart attack, stroke, and cardiovascular-related deaths, according to a study published today in the European Heart Journal.

Xylitol, a sugar alcohol naturally found in small amounts in fruits and vegetables, is also produced by the human body. As an additive, it resembles sugar in taste and appearance but contains 40% fewer calories. It is used in much higher concentrations than those found in nature in sugar-free gum, candies, toothpaste, and baked goods. Additionally, it is often present in products labeled as "keto-friendly," particularly in Europe.

Last year, the same research team identified a similar association with the popular sugar substitute erythritol. The use of sugar substitutes has increased a lot over the past ten years because people are worried about rising obesity rates.
"We're incorporating these substances into our diets, and the individuals most likely to consume them are also the ones most at risk for heart attack and stroke, such as those with diabetes," said Dr. Stanley Hazen, lead author and chair of cardiovascular and metabolic sciences at Cleveland Clinic’s Lerner Research Institute.

Many heart attacks and strokes occur in individuals without known risk factors such as diabetes, high blood pressure, or elevated cholesterol levels. The research team began studying sugar alcohols naturally found in the human body to determine if these compounds could predict cardiovascular risk in such individuals. In the study, the investigators measured the levels of naturally occurring xylitol in the blood of over 3,000 participants after overnight fasting. They discovered that individuals with xylitol levels in the top 25% had approximately double the risk of heart attack, stroke, or death over the next three years compared to those in the bottom 25%.

The researchers also sought to understand the underlying mechanisms. They fed xylitol to mice, added it to blood and plasma in the lab, and gave a xylitol-containing drink to 10 healthy volunteers. In all these cases, xylitol appeared to activate platelets, the blood components responsible for clotting, according to Hazen. Blood clots are the main cause of heart attacks and strokes.

"Just a few minutes of contact with xylitol can make platelets, which help blood clot, much more likely to form clots," Hazen explained..

The next question is what causes elevated levels of naturally occurring xylitol in some people and how to reduce it, noted Dr. Sadiya Khan, a cardiologist at Northwestern Medicine Bluhm Cardiovascular Institute and professor of cardiovascular epidemiology at Northwestern Feinberg School of Medicine, who was not involved in the study.

Much more research is needed, Hazen stated. In the meantime, he advises patients to avoid consuming xylitol and other sugar alcohols, which all end in 'itol.' Instead, he recommends using modest amounts of sugar, honey, or fruit to sweeten food, adding that toothpaste and one stick of gum are probably safe since they contain very little xylitol.

The report had some key limitations.