Common Sugar Substitute Linked to Increased Risk of Heart Attack

In a recent study published in the European Heart Journal, researchers from the Cleveland Clinic have raised alarms about the potential health risks associated with xylitol, a popular low-calorie sugar substitute. The study suggests that high consumption of xylitol may significantly increase the risk of heart attacks, strokes, and cardiovascular-related deaths.

Xylitol, a sugar alcohol found naturally in small quantities in fruits and vegetables, is widely used in sugar-free products such as gum, candies, toothpaste, and various keto-friendly foods. It is favored for its ability to mimic the taste of sugar while containing 40% fewer calories. 

The research team, led by Dr. Stanley Hazen, chair of cardiovascular and metabolic sciences at the Cleveland Clinic's Lerner Research Institute, conducted an extensive analysis involving over 3,000 participants from the U.S. and the UK. The study revealed that individuals with the highest levels of xylitol in their blood had nearly double the risk of heart attack, stroke, or death over the subsequent three years compared to those with the lowest levels.

Dr. Hazen explained that the team discovered xylitol's potential dangers while investigating new pathways linked to heart disease risk. "We examined blood samples from thousands of people and identified substances that were elevated among those who went on to have serious heart events. Xylitol was near the top of the list," he said.

The study's findings are particularly concerning given the increasing use of sugar substitutes in response to rising obesity rates and the demand for low-calorie, low-sugar products. Dr. Hazen emphasized that the very individuals most likely to consume these substitutes—those with diabetes or at risk for cardiovascular disease—are the ones who may be most adversely affected.

To understand the underlying mechanisms, the researchers conducted experiments on mice and added xylitol to blood and plasma samples in a lab setting. They also gave a xylitol-containing drink to ten healthy volunteers. The results showed that xylitol interacts with platelets, making them more prone to clotting. Blood clots are a leading cause of heart attacks and strokes, and the study suggests that xylitol may exacerbate this risk.

Dr. Matthew Tomey, a cardiologist at Mount Sinai Fuster Heart Hospital in New York City, who was not involved in the study, commented on the findings, stating, "These experiments are intriguing but do not definitively prove that platelet abnormalities are responsible for the link between xylitol and clinical events."

The study's implications extend beyond xylitol. Last year, the same research team found similar results for erythritol, another sugar alcohol used in many low-calorie and keto products. Both studies indicate that these sugar substitutes may enhance platelet activity, increasing the risk of clotting events.

Despite the concerning findings, the study did not establish a causal relationship between xylitol consumption and heart risk. Dr. Sadiya Khan, a cardiologist at Northwestern Medicine Bluhm Cardiovascular Institute, emphasized the need for further research to determine what causes elevated xylitol levels in some individuals and how to mitigate this risk.

In the meantime, Dr. Hazen advises patients to avoid consuming xylitol and other sugar alcohols, whose names typically end in 'itol.' He suggests using modest amounts of natural sweeteners like sugar, honey, or fruit instead. He also noted that the small amounts of xylitol found in toothpaste and gum are unlikely to pose significant risks.

The World Health Organization has also weighed in on the issue, advising consumers to avoid artificial sweeteners for weight loss and calling for more research on their long-term toxicity. The Calorie Control Council, an industry association, has previously dismissed similar findings, stating that they contradict decades of research showing the safety of reduced-calorie sweeteners.

As the debate over the safety of sugar substitutes continues, experts agree that more comprehensive studies are needed to fully understand their impact on human health. In the meantime, consumers are urged to be cautious and consider the potential risks associated with high consumption of these seemingly harmless sweeteners.