Study: Low-calorie sweetener xylitol leads to heart attack and stroke

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The low-calorie sweetener xylitol, found in many reduced-sugar foods and consumer products such as chewing gum and toothpaste, may increase the risk of heart attack, stroke and death in people who consume the highest amounts of the sweetener, according to a new study.

“We gave healthy volunteers a typical drink containing xylitol to see how high the levels would rise, and they rose 1,000-fold,” said lead study author Dr. Stanley Hazen, director of the Center for Cardiovascular Diagnostics and Prevention at the Cleveland Clinic. Lerner Research Institute.

“When you eat sugar, your blood sugar may go up 10 or 20 percent, but not 1,000-fold,” said Hazen, who also directs the Cleveland Clinic’s Center for Microbiome and Human Health.

“Humanity has only experienced such high levels of xylitol in the last few decades, when we began to consume completely artificially produced and processed foods replaced with sugar,” he added.

In 2023, the same researchers found similar results for another low-calorie sweetener called erythritol, which is used as a filling sugar in stevia, monk fruit, and reduced-sugar keto products.

Further laboratory and animal studies presented in both articles showed that erythritol and xylitol can make blood platelets clot more easily. Clots can break off and travel to the heart, causing a heart attack, or to the brain, causing a stroke.

In the new study on xylitol, “differences in platelet behavior were observed even after a person consumed a moderate amount of xylitol in a beverage equivalent to a serving consumed in real life,” said Dr. Matthew Tomey, a cardiologist at Mount Sinai Fuster Heart Hospital in New York City who was not involved in the study.

“These experiments are interesting, but they do not prove by themselves that platelet abnormalities are responsible for an association between xylitol and clinical events,” said Tomey, who is also an assistant professor of medicine at the Icahn School of Medicine at Mount Sinai.

About 61% of all American adults will suffer from cardiovascular disease by 2050, according to a recent forecast from the American Heart Association. Reducing clotting activity is one of cardiologists’ main treatments, so any extra clotting of platelets is a bad sign, said Dr. Andrew Freeman, director of cardiovascular prevention and wellness at National Jewish Health in Denver.

“When someone has a heart attack, we give them aspirin or drugs like clopidogrel or Plavix to inhibit platelet activity. These sugar alcohols seem to increase platelet activity, which is concerning,” said Freeman, who was not involved in the new research.

“This is another indication that we should switch to water, closely followed by unsweetened tea or coffee,” he said.

Carla Saunders, president of the industry association Calorie Control Council, told CNN that the study results “contradict decades of scientific evidence supporting the safety and effectiveness of low-calorie sweeteners such as xylitol by global health and regulatory authorities. These findings are a disservice to those who rely on alternative sweeteners as a means of improving their health.”

Xylitol is as sweet as sugar but has less than half the calories. It is commonly used in sugar-free gum, mints, toothpaste, mouthwash, cough syrup, and chewable vitamin tablets. In larger quantities, it is often added to candy, baked goods, cake mixes, barbecue sauces, ketchup, peanut butter, puddings, pancake syrup, and more.

Xylitol is a sugar alcohol, a carbohydrate that occurs naturally in foods such as cauliflower, eggplant, lettuce, mushrooms, spinach, plums, raspberries and strawberries. However, the amount of xylitol found in such natural sources is tiny, Hazen said.

“If you actually do the math, you would need literally a ton of fruit to equal one diabetic cookie, which can contain about nine grams of xylitol, which is a typical amount on the label,” he said. “That would be like eating the amount of salt in a salt lick.”

However, for commercial use, xylitol is produced from corn cobs, birch trees or genetically modified bacteria.

“It’s sold as a so-called natural sweetener, and because xylitol doesn’t raise blood sugar, it’s also marketed as low-carb and ketogenic,” Hazen said.

Many professional associations also recommend xylitol as a sugar substitute for patients with obesity, diabetes or prediabetes to improve blood sugar control, he added.

“Yet people at risk for diabetes are among those most vulnerable to blood clots,” he said. “We are targeting the wrong people.”

The burden has increased over the past two decades, Hazen said, because the U.S. Food and Drug Administration recognizes sugar alcohols as “generally recognized as safe” (GRAS).

“Xylitol is cheaper to produce than cane sugar, so it’s becoming more widely used as a sugar substitute in foods. Some 12-ounce beverages that use xylitol as their primary sweetener can contain 30 grams or more,” he said. “You can even buy it in bulk at the grocery store, where they’ll tell you you can use it as a 1:1 substitute for sugar in home cooking.”

Studies have shown that some artificial sweeteners can have a negative impact on metabolism, causing the body to require more calories and making it more difficult to lose weight.

The aim of the study, published Thursday in the European Heart Journal, was to find unknown chemicals or compounds in a person’s blood that could predict the risk of a heart attack, stroke or death within the next three years.

To do this, Hazen and his team analyzed 1,157 blood samples from people who were screened for heart disease between 2004 and 2011. They also examined another batch of blood samples from more than 2,100 people who may also have been at high risk for heart disease.

They found a number of alcohol sugars that appear to affect cardiovascular function, including xylitol and erythritol. Erythritol is the predominant ingredient by weight in many stevia and monk fruit products.

An erythritol study conducted in February 2023 found that the risk of heart attack and stroke almost doubled within three years when people had the highest levels of erythritol in their blood.

In the new study on xylitol, the results were essentially the same: People with the highest xylitol levels had almost twice the risk of heart attack, stroke and death compared to those with the lowest levels, Hazen said.

“There is a receptor on our platelets that we don’t yet understand that recognizes this molecule and signals the platelets to be more likely to clot,” he said. “Our taste buds can’t tell the structural difference between sugar and these other sweeteners, but our platelets obviously can.”

The World Health Organization warned consumers in 2023 against using artificial sweeteners for weight loss and called for further research into the long-term toxicity of low-calorie and no-calorie sweeteners, the study said.

“Through their work, the researchers have shed light on the safety of sugar substitutes. There is still more to learn,” said Tomey of Mount Sinai. “In the meantime, it is important to remember that sugar substitutes are not a substitute for a serious commitment to the various elements of a healthy diet and lifestyle.”