It's bad news for those who like a sweet brew.

While you may think opting for a sweetener instead of a teaspoon of sugar is better for your health, it's been found that certain sweeteners could have a negative effect on brain healthin later years.

A 2024 study, published in the journal Neurology, found a high consumption of sugar in adults appears to be linked to an increased dementiarisk.

Among those with the highest intake, that equalled to "about 1.6 years of ageing". In a more recent study, those under 60 were found to be at risk too.

The high consumption of artificial sweeteners can put younger adults at risk too, according to the research. The study, which followed 12,772 adults with an average age of 52 for a mean of eight years, found that some artificial sweeteners appeared to be linked to faster cognitive decline.

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Scientists looked at the following sweetners effects on participants brain health:

• aspartame,


• saccharin,


• acesulfame-K,


• erythritol,


• xylitol,


• sorbitol, and


• tagatose

It was found that only tagatose did not have a link to faster cognitive decline in the study. At the start, participants filled out questionnaires about their diets and were then split into three groups: low, medium, and high sweetener consumption.

Those placed in the lowest group consumed around 20 milligrams (mg) a day on average, while the highest group was as high as 191mg a day. Each group also took cognitive tests at the beginning, middle, and end of the study which were designed to assess six cognitive factors including memory, word recall, and verbal fluency.

Taking into considerations factors such as age, gender, and blood pressure, the research showed a link between a higher consumption of six low- and no-calorie sweeteners (LNCSs) and dementia risk, especially among under-60s.

According to Huffington post, those in the higher-consumption group experienced cognitive decline 65% faster than those in the lowest-LNCS consuming group. The middle group experienced cognitive changes 35% more quickly compared to those who consumed the fewest LNCSs.

"Daily consumption of LNCs was associated with accelerated decline in memory, verbal fluency and global cognition," the paper read and this effect seemed to be stronger among those with diabetes.

Study author Professor Claudia Kimie Suemoto explained: "While we found links to cognitive decline for middle-aged people both with and without diabetes, people with diabetes are more likely to use artificial sweeteners as sugar substitutes. More research is needed to confirm our findings and to investigate if other refined sugar alternatives, such as applesauce, honey, maple syrup or coconut sugar, may be effective alternatives."

Professor Suemoto said "low and no-calorie sweeteners are often seen as a healthy alternative to sugar, however our findings suggest certain sweeteners may have negative effects on brain health over time," but the researchers themselves noted that there is more that needs to be done to work out what this data - which only proves an association not a cause - means.

The NHS states that "all sweeteners in Great Britain undergo a rigorous safety assessment before they can be used in food and drink. All approved sweeteners are considered a safe and acceptable alternative to using sugar". While

The International Sweeteners Association (ISA) further shared in a statement that said: "This research is an observational study, which can only show a statistical association, not a direct cause-and-effect relationship. The reported link between sweetener consumption and cognitive decline does not prove that one causes the other," according to The Guardian.

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