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Artificial sweetener erythritol linked to heart attacks and strokes

Lab experiments show a popular sweetener can prompt clot formation in human blood, while research also links the product with a raised risk of heart attack and stroke

By Clare Wilson

27 February 2023

Multicolored ice cream - one sweetener added to some ice creams may raise the risk of heart attacks

Erythritol, a sweetener added to many low-calorie foods including ice creams, may raise the risk of blood clots and heart attacks

kajakiki/iStockphoto/Getty Images

A commonly used sweetener called erythritol has been linked with a higher rate of heart attacks and strokes.

The claim comes after researchers spotted a correlation between cardiovascular problems and the concentration of erythritol in the blood. It is supported by laboratory work on animals, and by tests on human blood samples that show the sweetener can make blood clots more likely.

Medical advice is that we should try to eat less sugar to stay a healthy weight, and that food and drink containing sweeteners are better for us than products containing natural sugars.

Erythritol has only relatively recently become an artificial additive in foods. It is a type of sugar alcohol that is about 70 per cent as sweet as the same weight of sugar, but that has almost no calories. Along with other sugar alcohols, erythritol is found at low levels in many fruits and vegetables, and can also be made naturally in our bodies.

But erythritol is now being added to so many foods that some people have blood levels much higher than would occur naturally, says Stanley Hazen at the Cleveland Clinic in Ohio. It has become an increasingly common ingredient in drinks and foods that are marketed for weight loss or for low-carbohydrate diets. “It is one of the fastest growing artificial sweeteners,” says Hazen.

Hazen’s team began investigating the effects of erythritol by testing blood samples from two previous studies that tracked people’s rate of heart attacks or strokes.

The two studies looked at people who were at risk of these events because of health factors such as being overweight or having diabetes. One contained about 2100 people in the US and the other contained about 830 people in Europe.

Hazen and his colleagues discovered that those in the quarter with the highest levels of erythritol had a higher risk of heart attack or stroke than those in the lowest quarter, over three years. The risk was about twice as high between the two groups, once the figures had been adjusted to account for the fact that people who are more overweight or had worse health were more likely to be consuming more erythritol.

As what is termed “observational research”, the studies didn’t prove that erythritol was causing the higher risk – something else could explain the correlation. So the team then explored the effects of erythritol on blood, as both heart attacks and strokes can be caused by the formation of blood clots.

When eight volunteers considered at low risk of heart attack or stroke consumed food and drinks containing 30 grams of erythritol – such as half a litre of low-carb ice cream – their blood levels of the sweetener jumped from about 4 micromoles (a measure of concentration) to about 6000 micromoles, and remained high for several hours. “As soon as you drink an artificially sweetened drink, the levels swamp the normal levels in the blood,” says Hazen.

Erythritol was also found to promote clot formation in mice and when added to samples of human blood, at levels of 300 micromoles and 45 micromoles, respectively. “Everything suggests this is not just an innocent bystander, it’s directly causing an enhancement in the reactivity of blood platelets,” says Hazen.

But Duane Mellor, a spokesperson for the British Dietetic Association, says most people wouldn’t be eating high enough quantities of it to reach the levels tested for clotting effects in this study.

Mellor says the findings should not cause people to stop consuming food and drinks with the sweetener. “We need to reduce our sugar intake,” he says.

Journal reference

Nature Medicine DOI: 10.1038/s41591-023-02223-9

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