Xylitol, often referred to as ‘birch sugar’, is a so-called ‘sugar alcohol’ that is used as a low-calorie sweetener in various foods and beverages. Xylitol is valued in the food industry because it improves the texture, moisture and shelf life of products without leaving an aftertaste like other sweeteners. It is therefore sold in large quantities and advertised as a ‘natural sweetener’, as it is also found in small quantities in fruit or vegetables and can be produced by the body.
Classification and use of xylitol
Artificial sweeteners such as xylitol are classified as ‘Generally Recognised as Safe’ (GRAS) by health authorities in the USA and the European Union. Their use has been recommended by several guideline organisations for people suffering from obesity, diabetes and cardiovascular disease.
According to some studies, xylitol is also said to have an anti-caries effect. The sweetener is therefore not only marketed as a substitute for sugar, but also as an additional remedy against tooth decay, for example as an additive in toothpastes, lozenges or chewing gum.
Implementation and results of the study
Dr Marco Witkowski, cardiologist at the DHZC Clinic for Cardiology, Angiology and Intensive Care Medicine at the Charité Benjamin Franklin campus, spent several years at the Cleveland Clinic in Ohio, USA, investigating whether the consumption of xylitol increases the risk of serious cardiovascular diseases such as heart attacks and strokes.
To this end, blood samples from more than 3,300 cardiovascular patients were analysed. These patients were then observed over a period of three years. During this period, patients with high xylitol concentrations in their blood were significantly more likely to suffer strokes, so-called ‘cardiac events’ such as a heart attack or death.
This correlation was subsequently confirmed: Laboratory experiments and tests with healthy study participants showed that xylitol increases the reactivity of blood platelets, which promotes the formation of blood clots and can therefore increase the risk of cardiovascular disease. Specifically, it was found that the risk of serious cardiac events was increased by 57 per cent with elevated xylitol levels in the blood.
Increased risk also associated with erythritol
Back in 2023, Dr Marco Witkowski, MD, in a study led by the Cleveland Clinic in collaboration with the DHZC, showed in the journal ‘Nature Medicine’ that the sweetener erythritol is also associated with an increased risk of heart attack and stroke.
The current study now shows that the sweetener xylitol is also associated with an increased risk of blood clots forming. The results highlight the potential risks of the group of sugar alcohols, which includes xylitol and erythritol.
Rethink consumption
"Our research highlights the potential risks of xylitol and shows that sweeteners are not necessarily the harmless sugar alternative they are often thought to be. Especially for people with existing cardiovascular risks, the consumption of xylitol could harbour additional health risks,’ says Witkowski. "It is important that consumers are aware of these risks and reconsider their consumption of these sweeteners. If they are unsure, they should consult their doctor or nutritionist." Given the widespread use of xylitol in food and dental care products, the authors of the study believe it is important to further investigate the potential health risks.
Source: press release DHZC (in German only)
Link to the original publication: Xylitol is prothrombotic and associated with cardiovascular risk (Witkowski et al., 2024)
Link to the erythritol study: The artificial sweetener erythritol and cardiovascular event risk (Witkowski et al., 2023)