Sugar-Free Sweetener Linked to Higher Heart-Attack Risk

Xylitol, a common sweetener used in sugar-free candies, drinks, and baked goods, has been linked to a higher risk of heart attack and stroke, according to research being presented at the European Society of Cardiology’s annual meeting.

The findings were “initially coincidence,” says Mario Witkowski, PhD, a presenter and researcher at Charité University Hospital in Berlin.

After discovering that people with risk factors for cardiovascular disease seemed to have worse outcomes after consuming xylitol, Dr. Witkowski and his fellow researchers looked to see if the sweetener was associated with a higher risk of heart attack, stroke, or death in people with no known risk factors for heart disease.

“Indeed, it is,” he says.

Higher Xylitol Levels in the Blood Were Tied to Increased Heart Disease Risk

For the investigation, researchers analyzed data from two long-term studies: the Canadian Longitudinal Study on Aging (CLSA) and the European Prospective Investigation into Cancer (EPIC)-Norfolk. The total cohort comprised about 18,000 adults who were 61 years old on average. Blood tests allowed researchers to measure xylitol levels, rather than rely on participants to exactly recall their diets.

During the follow-up period, which was six years for CLSA and 30 years for EPIC-Norfolk, there were more than 8,600 cardiac events. The researchers discovered that higher circulating blood levels of xylitol were linked with a higher risk of major cardiovascular emergencies, including heart attack, stroke, and early death.

The risk varied by cohort group. In the CLSA group, the risk of a major heart disease event was 47 percent higher in those with the highest levels of xylitol than in those who had the lowest levels, after researchers adjusted for known risk factors like age, sex, smoking status, and diabetes.

In the EPIC-Norfolk cohort, the risk of major adverse cardiovascular events was 18 percent higher in those with the highest levels of xylitol than in those with the lowest levels.

It’s “hard to tell” how much xylitol people in the high-consumption groups were eating, Witkowski says. “It was not possible to quantify the daily intake exactly,” he says. “Since xylitol and other sweeteners are often hidden in processed foods, people may not even be aware of their actual sweetener intake.”

What Is Xylitol, Exactly?

Xylitol is a low-calorie sweetener used in many sugar-free or low-calorie foods. “Sugar alcohols like xylitol are sweet-tasting and low in calories,” says Kelly Johnson-Arbor, MD, a toxicologist at MedStar Health in Washington, DC.

“It is present in trace amounts in whole fruit,” says Jamie Alan, PhD, PharmD, an associate professor of pharmacology and toxicology at Michigan State University in East Lansing. Natural sources of xylitol include plums, strawberries, cauliflower, and pumpkin, Dr. Johnson-Arbor adds.

Xylitol is known for its beneficial effects on dental health. “It prevents growth of cavity-causing bacteria and also prevents plaque accumulation in teeth,” Johnson-Arbor explains. The sweetener shows up in a range of products, including:

• Sugar-free chewing gum
• Toothpastes
• Antibacterial mouthwash products
• Sugar-free candies
• Vitamins
• Breath mints
• Some peanut butters

Xylitol Has Been Linked to Heart and Brain Health Concerns in the Past

What’s Behind the Link?

More research is needed to understand a possible connection between xylitol and cardiovascular issues, but scientists have at least one theory: “Research suggests that xylitol activates platelets, which are a sticky substance in blood that stops bleeding,” says Sanjiv Patel, MD, an interventional cardiologist at MemorialCare Heart & Vascular Institute at Orange Coast Medical Center in Fountain Valley, California. “If it activates those platelets in the blood, it can form a clot anywhere in the body — including the brain, lungs, and heart.”

Witkowski says that’s the most likely explanation. “We have previously shown that xylitol can directly enhance platelet responsiveness — the ability to clump together — in human blood and that it enhances blood clot formation,” he says. That may explain why higher levels of xylitol in the blood are also linked with a higher risk of heart attack, stroke, and death, he says.

The Study Has Strengths and Limitations

The study included a large number of people across two different cohort studies, allowing researchers to analyze a lot of data.

But the research was observational and couldn’t prove that xylitol causes heart attack, stroke, or death — it simply found a link.

Should You Avoid Foods and Drinks Made With Xylitol?

“Although this association between xylitol exposure and heart disease may sound worrisome, the data supporting it remains limited, and much more research is needed to determine the exact relationship between xylitol and heart health,” Johnson-Arbor says.

Still, Dr. Patel says it’s understandable to be wary of the sweetener, especially if you have underlying risk factors for cardiovascular disease. “If you don’t need it, cut it from your diet,” he says. “But if you really want to consume it, I cannot say we have strong enough evidence to suggest you shouldn't have it.”

Witkowski agrees that people with underlying risk factors should try to avoid having large amounts of xylitol. “Since large amounts of sweeteners are usually added to artificially sweetened foods, consumers should focus on whole foods and avoid processed foods,” he says.