NEW DELHI : A study published in the journal Neurology by the American Academy of Neurology has linked higher consumption of artificial sweeteners to faster cognitive decline, raising fresh questions about products long marketed as the “smart” sugar swap. Researchers tracked 12,772 adults (average age 52) over roughly eight years, estimating how much of seven sweeteners — aspartame, saccharin, acesulfame K, erythritol, xylitol, sorbitol and tagatose — each person consumed via food frequency questionnaires, then followed up with cognitive tests at the start, midpoint and end of the study.
The results: participants under 60 who ate and drank the most sweeteners showed a 62% faster decline in memory and thinking skills compared to those who consumed the least — a gap researchers say is roughly equivalent to a year and a half of extra brain aging. Even moderate consumers weren’t off the hook, showing a 35% faster rate of decline than the lowest-consumption group.
“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,” said study author Dr. Claudia Kimie Suemoto of the University of São Paulo.
The link was strongest among people with diabetes — a group especially likely to lean on sugar substitutes in the first place. “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,” Suemoto added.
Interestingly, the pattern didn’t hold for adults over 60 — no significant link showed up in that age group. Dr. Andrew Budson, a lecturer in neurology at Harvard Medical School, called that finding “curious,” but cautioned against reading it as an all-clear. Cognitive decline naturally varies more widely among older adults, he noted, which makes smaller effects harder to detect statistically — not proof that sweeteners stop mattering after 60.
Sweeteners show up far beyond the sugar packet on your table — they’re baked into a huge share of ultra-processed foods and beverages, from diet sodas to protein bars to “sugar-free” everything. Which means most people consuming them probably have no real sense of their daily total. Worth checking the label next time you reach for that diet cola.
