Consuming a drink with erythritol — an artificial sweetener used to add bulk to stevia and monk fruit and to sweeten low-carb keto products — more than doubled the risk of blood clotting in 10 healthy people, according to a new pilot study.
Clots can break off blood vessels and travel to the heart, triggering a heart attack, or to the brain, triggering a stroke. Previous research has linked erythritol to a higher risk of stroke, heart attack and death.
“What is remarkable is that in every single subject, every measure of platelet responsiveness (clotting) went up following the erythritol ingestion,” said lead study author Dr. Stanley Hazen, director of the Center for Cardiovascular Diagnostics and Prevention at the Cleveland Clinic Lerner Research Institute.
Consuming a drink with an equal amount of glucose, or sugar, did not affect blood platelet activity in another group of 10 people, said Hazen, who is also the Jan Bleeksma chair in vascular cell biology and atherosclerosis at the Cleveland Clinic.
“This is the first direct head-to-head comparison of the effects of ingesting glucose versus ingesting erythritol on multiple different measures of platelet function,” Hazen said. “Glucose doesn’t impact clotting, but erythritol does.”
While small, the study was “very intriguing and interesting,” said Dr. Andrew Freeman, director of cardiovascular prevention and wellness at National Jewish Health in Denver.
“I’m not saying we need to cease using these sugar alcohols immediately, but this line of research certainly begs the question: Are they safe or not?” said Freeman, who was not involved in the research.
In response to the study, the Calorie Control Council, an industry association, told CNN that 30 years of science has shown erythritol to be a “proven safe and effective choice” for sugar and calorie reduction.
“Consumers should interpret the results of this pilot with extreme caution. The limited number of participants, a total of 10, were given an excessive amount of erythritol, nearly quadruple the maximum amount approved in any single beverage in the United States,” the council’s president, Carla Saunders, said in an email.
However, the amount of erythritol used in each drink in the study — 30 grams — was the equivalent of what is included in typical sugar-free sodas, ice creams or muffins, of which people often eat more than one, Hazen said.
“This research raises some concerns that a standard serving of an erythritol-sweetened food or beverage may acutely stimulate a direct clot-forming effect,” said study coauthor Dr. Wai Hong Wilson Tang, research director for heart failure and cardiac transplantation at the Cleveland Clinic, in a statement.
What are sugar alcohols?
Like sorbitol and xylitol, erythritol is a sugar alcohol, a carb found naturally in many fruits and vegetables. The human body also makes erythritol as a byproduct of glucose metabolism but only in small quantities.
Artificially manufactured in massive quantities, erythritol has no lingering aftertaste, doesn’t spike blood sugar and has less of a laxative effect than some other sugar alcohols. It has about 70% of the sweetness of sugar and is considered zero calorie, according to experts.
Erythritol is the largest ingredient by weight in many “natural” stevia and monk fruit products, Hazen said. It looks and tastes like sugar and can be used for baking. It is also a key ingredient in many keto-friendly products including ice cream, Hazen said.
“If you look at nutrition labels on many keto ice creams, you’ll see ‘reducing sugar’ or ‘sugar alcohol,’ which are terms for erythritol,” he told CNN in an earlier interview.
“You’ll find a typical pint has somewhere between 26 and 45 grams in it.”
Artificially created erythritol, along with its cousins, are considered “generally recognized as safe,” or GRAS, by the US Food and Drug Administration.
Series of studies show similar results
The new study, published Thursday in the journal Arteriosclerosis, Thrombosis, and Vascular Biology, asked 20 participants to fast overnight in preparation for a morning blood draw. Next, they were given a drink with either 30 grams of erythritol or 30 grams of sugar. After 30 minutes, blood was drawn again.
Levels of erythritol in the blood rose by a thousandfold after the one drink with that substance, while blood sugars rose a small amount after the drink containing glucose. However, it was the change in platelet activity that was startling, Hazen said.
“We saw enhanced clotting, using measures of how quickly clots will occlude a vessel or stop blood flow, which is like a model of a heart attack or a stroke,” he said.
Similar results appeared in a 2023 study by Hazen and his colleagues in which eight healthy volunteers also consumed the same amount of erythritol and saw a thousandfold spike of the substance in their blood.
“(Erythritol) remained elevated above the threshold necessary to trigger and heighten clotting risk for the following two to three days,” Hazen said at the time.
That study also analyzed the blood of more than 4,000 people in the United States and Europe and found that those with the highest levels of erythritol were twice as likely to experience a heart attack or stroke.
“What we’re seeing with erythritol is the platelets become super responsive: A mere 10% stimulant produces 90% to 100% of a clot formation,” Hazen said.
The studies were done in healthy people without chronic disease; however, the study’s findings still apply for the future, Hazen said.
“However, if you look at middle-aged America, the average person has two to three risk factors for heart disease, and 70% of us are going to develop heart disease in our lifetime, so maybe we should all be considering action,” he said.
When it comes to the risk of cardiovascular disease, occasional sugar-sweetened treats in small amounts may be preferable to consuming drinks and foods sweetened with the sugar alcohols, he said. That’s especially true for anyone at highest risk for clotting, heart attack and stroke — such as those with existing cardiac disease or diabetes.
“Cardiovascular disease builds over time, and heart disease is the leading cause of death globally,” he said. “We need to make sure the foods we eat aren’t hidden contributors.”
