The researchers noted that xylitol is not commonly used in ketogenic or sugar-free foods in the U.S., but is widely used in other countries. “We were trying to find another pathway that naturally occurs in the body that contributes to heart disease — the next cholesterol,” said Hazen, who also serves as chair of cardiovascular and metabolic sciences at the Cleveland Clinic’s Lerner Research Institute. “And our belief is that sugar alcohols like erythritol and xylitol are associated with causing heart disease, or at least with the occurrence of future heart attacks.”
The same research team Similar links Last year, a link between erythritol and cardiovascular risk was revealed.
Use of sugar substitutes is on the rise
The survey results are as follows: The popularity of ketogenic and low-carb diets has led to a rise in alternative sweeteners touted as “natural,” with the use of sugar alcohols such as xylitol on the rise. Xylitol products sold about $1.19 billion. The market is expected to reach about $1.48 billion in 2021 and grow to about $1.48 billion by 2030, according to research firm Custom Market Insights.
“We’ve had an extraordinary situation in the last 10 to 20 years where humans have been exposed to levels of xylitol that we’ve never experienced before in our evolutionary history,” Hazen said.
The findings call into question the common perception that sugar alcohols such as xylitol and erythritol are healthy, natural sugar substitutes. Although sugar alcohols are considered natural because they are produced in the body as part of energy metabolism, cells produce much smaller amounts of them. These sugar alcohols are produced industrially using bacteria and yeasts that go through a brewing or fermentation process to produce chemicals that trick the taste buds, Hazen said.
“Despite being a natural compound, it’s being used in a very unnatural way and the levels are so high that they can’t occur under normal conditions in our bodies,” Hazen said.
The researchers also found that elevated xylitol levels may be more damaging to the heart than cholesterol: A diet high in cholesterol can raise blood cholesterol levels by 10 to 30 percent, Hazen said.
The researchers found that eating products high in xylitol increased blood levels of the chemical by 1,000-fold, or 100,000 percent, for four to six hours.
In other words, among the thousands of patients Hazen sees in his preventive cardiology clinic, those in the top 25 percent for cholesterol have a 30 percent higher risk of developing cardiovascular disease than those in the bottom 25 percent. But those in the top 25 percent for xylitol blood levels have a 200 percent higher risk of developing cardiovascular disease than those in the bottom 25 percent.
The Calorie Control Council, which represents manufacturers and suppliers of low- and reduced-calorie foods and beverages, rejected the study’s findings.
“The findings of this study run counter to decades of scientific evidence from health and regulatory agencies around the world demonstrating the safety and effectiveness of low-calorie sweeteners such as xylitol,” the council’s president, Carla Sanders, said in a statement.
“Xylitol has been a trusted source of great-tasting, low-calorie sweetener for over 60 years. It has proven dental benefits, including preventing plaque buildup and tooth decay, and is found naturally in foods such as strawberries, lettuce and oats,” she said.
“This study contributes to the growing literature on the physiological problems that may be caused by artificial sweeteners.” Marion Nestle“Researchers are finding one problem after another, and now it’s xylitol,” the New York University professor emeritus of nutrition wrote in an email.
She thinks the study needs to be repeated, but suggests that xylitol may not be harmless. The benefits of artificial sweeteners in general are unclear, she writes.
“It’s starting to seem more and more risky,” she wrote. “I’d like to avoid it, but I don’t like the taste anyway.”
Rob Van DamA professor of exercise and nutritional sciences at George Washington University said the findings are compelling and add to existing research on the risks of artificial sweeteners, but that because the study used blood from fasting people, which likely contained xylitol produced metabolically in the body, the scientists may not have been able to properly test the link between ingested xylitol and heart risk.
“So the question is, do elevated xylitol levels really reflect a bad dietary intake of xylitol,” Van Dam asked, “or is it just that there’s something wrong with people’s metabolism that’s leading to elevated xylitol levels?”
The researchers were aware of this problem and conducted a follow-up experiment in which they gave 10 subjects xylitol and water to see what happened to their platelets, and observed that the platelets appeared to clump together more.
“I don’t think that in itself is a big concern, but there’s accumulating evidence that some of the artificial sweeteners may not be as harmless as we thought,” Van Dam said. “If it was something that people didn’t consume a lot of, no one would be too concerned. But this is something that hundreds of millions of people are exposed to, sometimes every day, and any evidence that raises concerns is very relevant to public health.”
Hazen said the study is alarming given that sugar substitutes are widely recommended in the medical community as an alternative to sugar for people who are obese or trying to lose weight, or who have diabetes or metabolic syndrome.
“I hope this is a call to action for fellow researchers to start studying this issue, because this is a huge public health concern given how much of this stuff we’re putting into the food pyramid, assuming it’s safe,” Hazen said.
