Certain Artificial Sweeteners May Accelerate Cognitive Decline

Recent research published in Neurology highlights potential long-term effects of some sugar substitutes on brain health. The study investigated seven common low- and no-calorie sweeteners—namely aspartame, saccharin, acesulfame-K, erythritol, xylitol, sorbitol, and tagatose—and their association with cognitive decline.

The research analyzed data from 12,772 adults across Brazil over an average period of eight years. Participants reported their dietary habits, including artificial sweetener consumption, which was measured in daily intake. The study categorized consumption levels into three groups, with the highest group consuming roughly 191 mg per day—equivalent to one can of diet soda—while the lowest consumed about 20 mg daily.

Throughout the study, cognitive abilities such as verbal fluency, memory, processing speed, and language skills were assessed through regular cognitive tests administered at baseline, midway, and end of the follow-up. Results indicated that individuals with the highest intake of certain sweeteners experienced faster declines in overall cognitive functioning, with declines equivalent to about 1.6 years of aging compared to those with the lowest intake. The decline was especially pronounced in participants under 60 and in those with diabetes, suggesting a possible heightened vulnerability in these groups.

Artificial sweeteners linked to this decline include aspartame, saccharin, acesulfame-K, erythritol, sorbitol, and xylitol. Interestingly, tagatose did not show any association with cognitive deterioration. Researchers noted that these sweeteners are predominantly found in processed foods like flavored waters, sodas, energy drinks, yogurts, and low-calorie desserts.

While the findings do not establish causation, they raise concerns about the long-term neurological impacts of artificial sweeteners, which are often viewed as healthier sugar alternatives. Dr. Claudia Kimie Suemoto from the University of São Paulo emphasized that although these sweeteners are popular, evidence suggests they could negatively affect brain health over time. The study’s authors caution that more research is necessary to confirm these results and explore other sugar substitutes such as honey, maple syrup, or coconut sugar as potential healthier options.

Limitations of the research include reliance on self-reported dietary data and the exclusion of certain sweeteners. Nonetheless, this study adds to a growing body of evidence urging caution in the consumption of artificial sweeteners, especially among middle-aged adults and those with existing health conditions.