A new study links sugar substitutes to heart disease. What you need to know
Erythritol is a sugar substitute found in many low-calorie and diet-friendly foods and drinks. But new research suggests the compound may have an unexpected link to heart disease.
The study, published last week, suggests that erythritol may play a role in blood clotting, and consuming a large amount of erythritol can increase the risk for two days or more afterward. While that link isn't conclusive, experts tell TODAY.com it's worth keeping an eye on how much erythritol — and other sugar substitutes — you consume on a regular basis.
What is erythritol?
Erythritol is what's known as a reducing sugar or sugar alcohol, Dr. Stanley Hazen, chairman for the department of cardiovascular and metabolic sciences in the Lerner Research Institute and co-section head of preventive cardiology at the Cleveland Clinic, tells TODAY.com
“It tastes very similar to sugar, but we don’t derive calories from it,” he explains.
Sugar alcohols, including erythritol, and other artificial sweeteners “have actually been fairly well studied because we’ve seen such an increasing use of them in the food supply,” Whitney Linsenmeyer, Ph.D., R.D., a spokesperson for the Academy of Nutrition and Dietetics and assistant professor at Saint Louis University, tells TODAY.com.
That long-term research has been mixed overall, but the Food and Drug Administration considers sugar alcohols “perfectly safe for human consumption,” she says.
It's a particularly popular sugar substitute because it behaves a lot like sugar in cooking or baking, Hazen says, and it can be used as a "bulking sugar" in products alongside other sweeteners — like stevia, monk fruit and other sugar alcohols — to make them taste a bit better.
Our own bodies also make erythritol in response to high glucose levels, Susie Swithers, Ph.D., professor in the department of psychological sciences at Purdue University, tells TODAY.com. It usually stays inside your cells and helps to make energy, but some of it leaks out into your bloodstream, Hazen adds, and different people have different circulating levels of erythritol in their bodies.
Erythritol is also found in some foods naturally, like watermelon and some fermented foods, Hazen says. However, in those foods it’s present in much smaller amounts than you’d find in an artificially sweetened drink or dessert, he adds.
For those reasons, it's debatable whether or not erythritol falls into the "artificial" sweetener category, Swithers explains, and products that have erythritol in them may say they contain only natural sweeteners on the packaging.
Companies still need to list erythritol in the full list of ingredients, though, she says. But if there are two or more types of sugar alcohols in a product, the label won't necessarily list them independently, Linsenmeyer says. Instead, they might be listed simply as "sugar alcohols."
But when we're talking about erythritol in day-to-day life, we usually talk about it as an artificial sweetener commonly found in diet foods and drinks. And it's become increasingly popular over the last decade.
More and more, erythritol is "being used as the carrier with other artificial sweeteners," Hazen says. "In the keto food world and in the zero sugar world, it has been the darling of artificial sweeteners and really taken off in the past 10 years."
Common side effects of erythritol
The reason why sugar alcohols are so useful as alternative sweeteners is that "our bodies do not metabolize them particularly well," Swithers explains. "So we consume them and then we excrete them. And because we're not metabolizing them, we're not getting any energy or calories from them."
But that also leads to the "gastrointestinal distress" that some people might feel after ingesting a large amount of food or drinks containing sugar alcohols, she says.
So, as with any of the sugar alcohols, erythritol can cause gastrointestinal side effects such as:
Compared to other sugar alcohols, though, erythritol tends to cause these issues less often, Hazen says. "That's really more frequent with xylitol," Linsenmeyer says. And products containing sorbitol and mannitol must have a warning on the label that they "may cause a laxative effect," the FDA says.
Erythritol and heart issues
A new study, published in Nature Medicine last week, found a strong association between erythritol and the risk for heart attacks and strokes.
In the first part of the study, researchers looked at blood test results from about 1,100 patients undergoing a cardiac risk assessment. They found that those participants with elevated levels of erythritol in their blood were more likely to have cardiac issues, such as heart attack or stroke, over a three-year period.
The researchers then repeated those findings in targeted analyses of 2,100 participants in the U.S. and 830 in Europe, all of whom were undergoing cardiac assessments for possible heart issues. From there, the researchers conducted lab studies and found that erythritol can induce platelet activity (which leads to clotting), and clotting itself in mice.
Finally, the researchers gave a group of eight healthy volunteers a drink containing erythritol and saw strikingly high levels of erythritol in their bodies for two days afterward.
"The plasma levels of erythritol were sky high," says Hazen, one of the study authors, "and above the threshold at which it causes heightened clotting risks." (Participants were given a 30 mg dose of erythritol, which is roughly equivalent to the amount in a pint of keto-friendly ice cream or a few erythritol-containing cookies, Hazen says.)
Together, the study findings suggest a significant association between erythritol and an increased risk for heart attack, stroke and death. And they indicate that eating or drinking erythritol may directly raise the risk for blood clots for days after consuming that product.
While the new research doesn't conclusively prove a causal link between erythritol and cardiac issues, "it definitely raises a level of concern," says Swithers, who was not involved with the study.
"It's a very compelling study," Linsenmeyer agrees. "It's strong and it's looking at (the link) from different angles, but it's not conclusive."
Swithers says the results in healthy participants were particularly striking: "It’s remarkable that the levels (of erythritol) are so high for so long."
“The results of this study are contrary to decades of scientific research showing reduced-calorie sweeteners like erythritol are safe, as evidenced by global regulatory permissions for their use in foods and beverages, and should not be extrapolated to the general population, as the participants in the intervention were already at increased risk for cardiovascular events,” said Robert Rankin, executive director of the Calorie Control Council, an association that represents the low- and reduced-calorie food and drink industry.
"Erythritol is a proven safe and effective choice for sugar and calorie reduction and, for more than 30 years, has been used in reduced-sugar foods and beverages to provide sweetness, as well as enhance their taste and texture," Rankin continued in a statement. "Along with exercise and a healthy diet, reduced-calorie sweeteners are a critical tool that can help consumers manage body weight and reduce the risk of non-communicable diseases, such as cardiovascular disease.”
Hazen emphasizes that the findings aren’t just about erythritol found in foods. For instance, the initial patient data came from tests performed between 2004 and 2011, which predates the current prevalence of erythritol-containing products, he explains.
And he stresses that these results shouldn’t be cause for alarm because, in the long-term, “we’re going to be able to turn this into a way of better understanding heart disease and helping to prevent heart disease.”
What to know before eating or drinking products containing erythritol:
If you're someone who consumes a lot of sugary foods or drinks, swapping some of them out with artificially sweetened ones can be part of a plan to reduce your intake of those products, Linsenmeyer says. But, ultimately, you should aim to limit how much of those artificially sweetened products you consume as well.
"Ideally, we would not be relying heavily on artificial sweeteners," she says, noting that she would generally steer people to water, tea and other beverages that don't contain those sweeteners.
"But that's just not reality for a lot of people," she says. "So I think (artificial sweeteners) absolutely have a place, and they're a tool that we can use for patients." The concerns start to come in when people are consuming large amounts of these ingredients because, as mentioned above, they can cause gastrointestinal issues.
To avoid those possible gastrointestinal effects, people should aim to eat no more than 10 to 15 grams of sugar alcohols per day, Linsenmeyer advises.
It might make more sense to fully cut out erythritol for people who already have known risk factors for blood clots or heart disease, Swithers says. But the research is still developing. And before making specific recommendations, “we really do need to know more about this,” she says.
"I'm suggesting to my patients to try to avoid the artificial sweeteners and to just use moderation with a regular sweetener, whether it be a little bit of honey, fruit or sugar," Hazen says.
Linsenmeyer agrees, noting that people with diabetes and heart disease can absolutely safely eat traditional sugars. "It just has to be in much smaller quantities and managed with their medications and the rest of the food that they're eating," she explains.
But that's not going to work if you're trying to follow a keto diet, Hazen adds. And if you regularly eat keto-friendly ice cream or chocolate that's sweetened with erythritol, the new study should be a reminder to do so in moderation, Linsenmeyer says.
Still, you don't need to completely cut those foods out of your diet if you like them, Linsenmeyer says. "As with all things, enjoy them in moderation."
This article was originally published on TODAY.com