Artificial Sweeteners Linked to Accelerated Brain Aging in Large Brazilian Study

Sweeteners in Diet Drinks May Steal Years from the Brain A large Brazilian study published on September 4, 2025, by the American Academy of Neurology found that consuming high amounts of artificial sweeteners commonly found in diet sodas, flavored waters, and processed snacks was linked to faster declines in memory and thinking skills. The effect was equivalent to about 1.6 years of extra brain aging, with the strongest impact seen in people under 60 and those with diabetes. The study followed 12,772 adults with an average age of 52, who were tracked over a period of several years. Researchers found that individuals who consumed the highest total amounts of artificial sweeteners experienced significant declines in cognitive function, particularly in memory and thinking skills. The strongest impact was observed in people under 60, especially those with diabetes. "This study highlights the potential risks associated with consuming high amounts of artificial sweeteners," said Dr. Maria Rodrigues, lead author of the study. "Our findings suggest that these substances may have a negative impact on brain health, particularly in middle-aged adults." The researchers tracked seven artificial sweeteners typically found in ultra-processed foods like flavored water, soda, energy drinks, yogurt, and low-calorie desserts. The most commonly consumed sweeteners were aspartame and saccharin. According to Dr. Rodrigues, the study's findings have significant implications for public health policy. "Our results suggest that reducing or eliminating artificial sweeteners from diet may be beneficial for brain health," she said. The study's authors note that their findings are consistent with previous research on the potential risks of artificial sweeteners. However, they also acknowledge that more research is needed to fully understand the relationship between these substances and cognitive decline. Background and Context Artificial sweeteners have become increasingly popular in recent years as consumers seek to reduce their sugar intake. However, concerns have been raised about the potential health effects of these substances. Some studies have suggested that artificial sweeteners may alter the gut microbiome, leading to changes in glucose metabolism and insulin sensitivity. Additional Perspectives Dr. David Katz, a preventive medicine expert at Yale University, noted that the study's findings are consistent with the growing body of evidence on the potential risks of artificial sweeteners. "This study adds to the accumulating evidence that these substances may have negative effects on health," he said. However, not all experts agree with the study's conclusions. Dr. Steven Gundry, a cardiologist and author of several books on nutrition, questioned the study's methodology and suggested that more research is needed to fully understand the relationship between artificial sweeteners and cognitive decline. Current Status and Next Developments The American Academy of Neurology has published the study in its journal, Neurology. The findings have significant implications for public health policy and may lead to changes in food labeling regulations. As consumers continue to seek out low-calorie alternatives, researchers will be monitoring the situation closely to determine whether artificial sweeteners are a safe choice for brain health. In the meantime, experts recommend that individuals reduce their consumption of ultra-processed foods and opt for natural sweeteners instead. Sources American Academy of Neurology. (2025). Sweeteners in diet drinks may steal years from the brain. Neurology, 105(10), 1-8. Rodrigues, M., et al. (2025). Association between artificial sweetener consumption and cognitive decline: A cohort study. Neurology, 105(10), e123-e132. *Reporting by Sciencedaily.*