Overview

• Researchers tracked 12,772 Brazilian adults for about eight years and found that higher consumers of low- and no‑calorie sweeteners declined faster on repeated memory and thinking tests.
• Compared with the lowest intake group, the middle group declined 35% faster and the highest group 62% faster, roughly equivalent to 1.3 and 1.6 additional years of brain aging, with top intake near one diet soda’s worth of aspartame a day.
• Aspartame, saccharin, acesulfame‑K, erythritol, xylitol and sorbitol were linked to faster decline, while tagatose showed no association.
• The associations were strongest in people with diabetes and were observed mainly in participants under 60, with no significant link detected in those 60 and older.
• Authors emphasize the study cannot prove causation and note limits such as self‑reported baseline diet, no repeat measures, and no brain imaging; they are pursuing neuroimaging studies as industry groups stress the findings show correlation, not cause.