Subscribe to CNN’s “Eat, But Better: Mediterranean Style.” Our 8-part guide shares delicious, expert-recommended eating habits that will boost your health for a lifetime..
CNN
—
Xylitol, a low-calorie sweetener used in many low-sugar foods, gum, toothpaste and other consumer products, may nearly double people’s risk of heart attack, stroke and death if they consume the highest amounts of the sweetener, a new study finds.
“We gave healthy volunteers a common drink that contained xylitol to see how much its levels increased, and they went up 1,000-fold,” said Dr. Stanley Hazen, director of the Cleveland Clinic’s Center for Cardiovascular Diagnostics and Prevention and the study’s lead author. Learner Research Institute.
“When you eat sugar, your blood sugar might go up 10 to 20 percent, but it doesn’t go up 1,000-fold,” says Hazen, who is also director of the Center for Microbiome and Human Health at the Cleveland Clinic.
“Humans have never experienced such high levels of xylitol before, except in recent decades when we began consuming processed foods that were entirely artificial and replaced sugar,” he added.
In 2023, the same researchers found similar results with stevia, monk fruit, another low-calorie sweetener called erythritol, which is used as a bulking sugar in keto low-carb products.
Additional laboratory and animal studies published in both papers found that erythritol and xylitol can increase the clotting of blood platelets, which can then break off and travel to the heart, causing a heart attack, or travel to the brain, causing a stroke.
The new xylitol study found that “we saw differences in platelet behavior even after ingesting small amounts of xylitol in a beverage, comparable to the amount typically consumed in daily life,” said Dr. Matthew Tomei, a cardiologist at Mount Sinai Fuster Heart Hospital in New York City, who was not involved in the study.
“These studies are intriguing, but they do not by themselves prove that platelet abnormalities explain the association between xylitol and clinical symptoms,” said Tomei, who is also an assistant professor of medicine at the Icahn School of Medicine at Mount Sinai.
According to a recent projection from the American Heart Association, about 61 percent of American adults will have cardiovascular disease by 2050. Suppressing blood clotting activity is a key treatment used by cardiologists, so more platelet clotting is a bad sign, said Dr. Andrew Freeman, director of cardiovascular disease prevention and wellness at National Jewish Health in Denver.
“After a heart attack, patients are given drugs like aspirin, clopidogrel and Plavix to suppress platelet activity, and these sugar alcohols appear to increase platelet activity, which is a concern,” said Freeman, who was not involved in the new study.
“This is another warning sign that people should switch to water, followed by unsweetened tea and coffee,” he said.
Carla Sanders, president of the industry group Calorie Control Council, told CNN that the study’s findings “run counter to decades of scientific evidence from health and regulatory agencies around the world demonstrating the safety and effectiveness of low-calorie sweeteners like xylitol. These findings are a disservice to people who rely on alternative sweeteners to improve their health.”
As sweet as sugar but with less than half the calories, xylitol is commonly used in sugarless gum, breath mints, toothpaste, mouthwash, cough syrup and chewable vitamins. It is also often added in large amounts to candy, baked goods, cake mixes, barbecue sauce, ketchup, peanut butter, puddings and pancake syrup.
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 in these natural sources is very small, says Hazen.
“If you do the math, it would literally take a ton of fruit to equal one diabetic cookie, which has the nine grams of xylitol that is typically listed on the label,” he said. “That’s like eating a lick of salt.”
However, commercially used xylitol is made from corn cobs, birch trees, or genetically modified bacteria.
“Xylitol is marketed as a so-called natural sweetener and is also marketed as a suitable sweetener for low-carb and ketogenic diets because it doesn’t spike blood sugar levels,” Hazen said.
Many professional organizations also recommend xylitol as a sugar substitute to improve blood sugar control for patients with obesity, diabetes and prediabetes, he added.
“But people at risk for diabetes are the people most vulnerable to thrombosis,” he says. “We’re targeting the wrong people.”
Hazen said exposure has increased over the past 20 years as the U.S. Food and Drug Administration has recognized sugar alcohols as generally recognized as safe (GRAS).
“Xylitol is cheaper to produce than cane sugar, so it’s increasingly being incorporated into foods as a sugar substitute. Some 12-ounce drinks that use xylitol as the primary artificial sweetener can contain more than 30 grams of xylitol,” he says. “Xylitol is recommended for use as a one-to-one replacement for sugar in home cooks, and it can also be purchased in bulk at grocery stores.”
Research has shown that some artificial sweeteners can backfire your metabolism, causing your body to take in more calories and making it harder to lose weight.
The study, published Thursday in the European Heart Journal, began as a way to find unknown chemicals or compounds in a person’s blood that might predict their risk of heart attack, stroke or death within the next three years.
To do so, Hazen and his team analyzed 1,157 blood samples taken from people who were being evaluated for heart disease between 2004 and 2011. They also tested additional blood samples taken from more than 2,100 people who may have been at high risk for heart disease.
They found several alcoholic sugars that appear to affect cardiovascular function, including xylitol and erythritol, the main ingredient by weight in many stevia and monk fruit products.
A February 2023 study on erythritol found that people who had the highest levels of erythritol in their blood had a nearly doubled risk of heart attack or stroke within three years.
The new study on xylitol found essentially the same results: People with the highest xylitol intake had nearly twice the risk of heart attack, stroke and death compared with those with the lowest intake, Hazen said.
“Platelets have a yet-to-be-identified receptor that recognizes this molecule and signals the platelets to be more likely to form blood clots,” he says. “While our taste buds cannot tell the difference between the structure of sugar and other sweeteners, platelets clearly can.”
The World Health Organization will warn consumers in 2023 to avoid artificial sweeteners for weight loss purposes and will call for more research into the long-term toxicity of low- and no-calorie sweeteners, the study said.
“Through their studies, researchers have shed light on the safety of sugar substitutes, and there is still much to learn,” said Tomei of Mount Sinai, “but it’s worth remembering that sugar substitutes are not a substitute for a serious commitment to several elements of a healthy diet and lifestyle.”
