An extensive observational study lasting eight years has uncovered significant connections between the consumption of artificial sweeteners and a marked decline in memory and cognitive skills among middle-aged adults. While many individuals opt for artificial sweetener options as a healthier choice, this recent research suggests that these alternatives may not be as beneficial as they are often portrayed. In fact, the findings indicate that regular consumption of certain sweeteners could lead to unexpected health consequences.
The study, published in the journal Neurology on September 3, 2025, explored the relationship between low- and no-calorie sweeteners (LNCSs) and cognitive decline. Researchers tracked a cohort of over 12,500 Brazilian adults, with an average age of 52, over the eight-year span. Participants self-reported their dietary intake of seven different LNCSs, and cognitive tests were administered periodically to evaluate memory, language, and thinking skills.
While the sweetener tagatose showed no correlation with cognitive decline, the study identified six other sweeteners linked to deteriorating cognitive abilities:
Aspartame Saccharin Acesulfame-K Erythritol Sorbitol XylitolNotably, the decline in cognitive function was particularly pronounced in memory and verbal fluency. Additionally, participants with diabetes who consumed LNCSs experienced an accelerated decline in memory. The study revealed that individuals under 60 showed a greater impact from sweetener consumption, emphasizing the importance of monitoring sweetener intake earlier in life to mitigate potential cognitive issues later.
For participants consuming higher quantities of the identified sweeteners, the study found their cognitive decline equated to an accelerated aging effect of approximately 1.6 years. Dr. Claudia Suemoto, a co-author of the study and an associate professor of geriatrics at the University of Sao Paulo, explained to TODAY.com, “Cognitive performance peaks around the third decade of life, between 25 and 30 years old, and after that, there is a very slow, gradual decline in function. Our study indicates that sweetener consumption may accelerate this natural process, even in middle-aged adults.”
Despite its significant findings, the study does have limitations. Not all artificial sweeteners were included in the research, and participants self-reported their dietary intake, which may introduce inaccuracies if individuals failed to recall their consumption accurately. Dr. Suemoto noted in a press release, “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.”
Importantly, while the study identifies a link between LNCSs and cognitive decline, it does not establish a direct cause-and-effect relationship. The International Sweeteners Association responded to the study, stating that observational research can only demonstrate statistical associations, not definitive causation. They emphasized that global authorities have consistently confirmed the safety of LNCSs, based on comprehensive safety assessments that consider a wide array of scientific evidence.
This groundbreaking research prompts a reevaluation of the long-term health impacts of consuming artificial sweeteners. As more individuals turn to these low-calorie options in pursuit of healthier lifestyles, understanding their potential effects on cognitive health is crucial. Ongoing research is essential to further explore the implications of sweetener consumption and to identify safer alternatives.
