Consuming high levels could cause your brain to age 1.6 years faster, impacting cognition and memory, with scientists warning that type two diabetics may be the most at risk
A new study has triggered alarm bells for scientists as artificial sweeteners, often seen as a healthier substitute for those trying to lose weight or have conditions like diabetes, may be putting people’s brain health at risk. In research published in the Neurology journal, scientists said that people consuming the highest amount of sweeteners sped up their cognitive decline and brain ageing by 62%.
For the study, the term ‘high levels’ of articial sweeteners was equivalent to just one diet fizzy drink a day. People having this amount of sweetener or more each day experienced a decline in their ability to remember and recall words.
These people also experienced faster ageing in terms of cognitive ability by 1.6 years. These results were more prominent in people under the age of 60 or diabetics, they found.
The study used data from the Brazilian Longitudinal Study of Adult Health. It followed 12,772 adults over an eight-year period. On average, participants had 20mg of artificial sweetener per day in the lowest group.
In the highest group, people had 191mg on average per day, roughly equivalent to one can of diet soda a day. Researchers tested multiple sweeteners but Sorbitol turned out to be the most commonly consumed, with an average of 64mg per day across participants.
Participants were tested on their memory, verbal fluency, recall and processing speed. Compared to those in the lowest group, the middle group saw a cognitive decline that was 35% faster, while the higher group had a 62% faster decline.
Lead study author Dr. Claudia Kimie Suemoto, associate professor of geriatrics and director of the Biobank for Aging Studies at the University of São Paulo’s Medical School in Brazil, explained: “People who consumed the most low- or no-calorie sweeteners showed a 62% faster global cognitive decline than those who consumed the lowest amount – that’s the equivalent of 1.6 – years of brain ageing.
“Participants in the middle tier had a 35% faster rate of global cognitive decline – which is about 1.3 years of ageing – than people who consumed the lowest amount of these sweeteners.
“Now, the study is only observational – I cannot say to you that artificial sweeteners cause cognitive decline. We do know, however, that these sweeteners are associated with worse cognitive trajectories.
She told Jornal da USP: “I used to consume a lot of sweetener, I like zero-calorie soft drinks, and I sweetened my coffee with sweetener. I always had this question about the relationship between sweeteners and cognitive decline, and this hypothesis caught my attention at the time when we did the work on ultra-processed foods, of which this is a continuation.”
The research examined seven different types of artificial sweetener. Six of these were connected to mental decline, whilst tagatose, a natural sugar present in dairy products and fruit, showed no clear effect.
Dr. Suemoto continued: “People with diabetes are more likely to consume artificial sweeteners as a substitute for sugar, so their overall exposure may be higher than people without diabetes.
“In addition, diabetes itself is already a strong risk factor for cognitive decline related to Alzheimer’s disease and vascular dementia, which probably makes the brain more vulnerable to harmful exposures.”
The researchers admitted their findings had some shortcomings. These included sweetener consumption only being measured at the beginning of the study so variations in how much participants were drinking weren’t measured.