Another popular low-calorie sweetener increases risk of heart attacks and strokes, Cleveland Clinic researchers find (2024)

CLEVELAND, Ohio — Consuming products sweetened with the sugar substitute xylitol increases the risk of cardiovascular events like heart attacks and strokes, says a new study by researchers at the Cleveland Clinic.

The results released Thursday provide further evidence of the dangers of sugar substitutes on the heart and vascular system. Last year, the same group published data that erythritol, another popular sugar substitute, was associated with similar risks to the heart.

Xylitol is a common sugar substitute used in sugar-free candy, gums, baked goods and oral products like toothpaste. For example, it’s found in sugar-free versions of Trident and Mentos gum, and is frequently added to gum, candy and toothpaste because it has been suggested by other studies to prevent tooth decay.

It is part of a group of alcohol-based sugars derived from plants, that also include erythritol, sorbitol and maltitol, all widely used in the food industry, as a low-calorie replacement for sugar in the United States and Europe.

Because their chemical structure is similar to that of sugar, they taste sweet. However, they are not processed by the body in the same way as sugar, and therefore contain fewer calories. This makes them increasingly common in diet foods aimed at diabetics and anyone attempting to reduce their sugar or calorie intake.

Although these sugars are naturally produced in small amounts by the body, the amount found in processed foods greatly exceeds what might be found in the blood naturally by as much as 1,000 times.

And it turns out that’s bad news for your heart— because those chemicals encourage the blood to form clots, explained Dr. Stanley Hazen, the Cleveland Clinic cardiologist who led the study.

Hazen likens the process to that of cholesterol. “Just like cholesterol if you eat a high cholesterol diet that can increase your cholesterol level and make you more prone to have a heart attack over decades -- well this is much faster.”

In fact, after ingesting it, plasma levels are high enough to increase your clotting risk for the next six hours, the doctor said.

“We were able to show that xylitol, at physiologic levels, would trigger an enhanced clotting risk - the same thing you would see with a heart attack or a stroke,” said Hazen.

Hazen and his colleagues saw this effect both in animals that were given xylitol enhanced food or water, and in people who were given beverages sweetened with xylitol.

He says that what is happening is that the sugar-like compounds are lowering the threshold for the activation of platelets - the components of blood that are responsible for the formation of clots. By ingesting them, they cause blood clots to form more easily, and much faster than they normally would.

Originally, Hazen says the researchers were not specifically targeting sugar substitutes, but simply looking for any chemicals in blood that could predict those people who were at increased future risk for heart attack stroke or death in a three-year period.

However, they came up with a list of candidate molecules and erythritol and xylitol were on it. They decided to investigate those first given the fact that these chemicals were quickly growing in popularity.

Last year, the group published similar data on the dangers of erythritol, the only difference being that instead of an increased clotting risk that lasted for a few hours, erythritol’s effects lasted for days.

“Xylitol hangs around for a shorter period of time, a matter of hours, but still, that’s a bad thing if you have a higher clotting risk if while the level is high in that four-to-six-hour window your likelihood of experiencing a heart attack doubles,” said Hazen.

This is especially the case when one considers that a lot of the people who are more likely to be eating the diabetic cookies or the diabetic candy that contains these sugar-substitutes are people with diabetes who are already at a higher clotting risk.

Furthermore, Hazen says there’s good reason to believe that the xylitol levels will remain higher longer in people with reduced kidney function, something common among diabetics,

This means, Hazen argues, that the diet industry is inadvertently putting the less healthy among us at greater risk.

“If you’re diabetic or obese of have something called metabolic syndrome, even our current regulatory guidelines are recommending the use of artificial sweeteners or sugar substitutes, and what we are seeing that rather than a healthy choice it appears to be quite the opposite.”

One of the big challenges for consumers is going to be knowing what sweeteners are actually in the products they are buying.

Currently, as long as manufacturers don’t make any specific claims about the product like “low-carb” or “zero-carb” they aren’t even required to put the sweetener on the label, and that’s something Hazen says has to change.

“They can lump it together and say “naturally sweetened” or “sugar alcohol content” and not even tell you what you’re ingesting,” said Hazen. “I hope that that changes in the future as more and more researchers publish papers that build on our story. People will start to see that this is a very significant public health issue ... we gotta get it right.”

Hazen says, however, it’s going to take some time to get the word out and get the diet industry on board.

The research is hard to do, but necessary, he says. There are eight types of alcohol sugars approved for use in the food and beverage industry, and while they have only looked at two of them, Hazen says it stands to reason that other artificial sweeteners could have similar effects. It’s one of the things his lab will be looking at next.

Meanwhile, he suggests that consumers, especially those at risk for heart disease or clotting disorders avoid these sugar-substitutes and stick to natural stuff instead.

“At this point I would argue, reach for a little bit of honey, or a little bit of sugar or fruit.”

Stories by Gretchen Cuda Kroen

• When you get a raise at the Cleveland Clinic, your bank of PTO shrinks
• Ohio State creates database for Alzheimer’s genetics research
• Immune therapy first developed for cancer is being tested in Cleveland for patients battling lupus
• A blood test for cancer: MediCLE
• Fighting cancer, not fires: blood test for up to 50 cancers helps protect those most at risk