Low-calorie sweeteners and sugar substitutes have been around since the early 1900s. The US FDA has approved sugar substitutes such as saccharin, sucralose, aspartame, xylitol, erythritol, stevia, and monk fruit for use as food additives. They offer the benefits of reduced blood sugar spike in people with diabetes and protection of the teeth from cavities and decay [1].
However, consumption of low- and no-calorie sweeteners (LNCSs) has been linked with adverse health outcomes, including negative impact on the gut microbiome and higher risk of heart attack, stroke, metabolic syndrome, obesity, migraine, and cancer. Nevertheless, not much is known about the association between consumption of LNCSs and cognition [1].
A recent study by Gonçalves NG et al., published in the journal “Neurology”, evaluated the link between consumption of LNCSs and cognitive decline. This was a longitudinal observational study including 12,772 participants (51.9 years, 54.8% women) who were followed up for ~8 years. Combined and individual consumption of 7 LNCSs (aspartame, saccharin, acesulfame k, erythritol, xylitol, sorbitol, and tagatose) were calculated using a food frequency questionnaire. Standard cognitive tests were administered every 4 years over three study periods (2008–2010, 2012–2014, and 2017–2019). Z-scores were estimated across these tests. Participants who consumed the highest amounts of LNCSs (191 mg/day) experienced a 62% faster decline in thinking and memory skills compared to those who consumed the lowest amounts (20 mg/day), which is equivalent of about 1.6 years of aging. The link was found in participants younger than 60 years and not in older adults and was stronger in those with diabetes [1-4]. (see Graphic)
(Source: 1. 7 sugar substitutes linked to 62% faster decline in thinking, memory skills. [Internet]. Cited 2025, September 19. Available from: https://www.medicalnewstoday.com/articles/7-sugar-substitutes-linked-62-faster-decline-thinking-memory-skills-aging; 2. Sugar substitutes Not so sweet for brain health – Medscape – September 04, 2025. [Internet]. Cited 2025, September 19. Available from: https://www.medscape.com/viewarticle/sugar-substitutes-not-so-sweet-brain-health-2025a1000nes; 3. Not so sweet: Some sugar substitutes linked to faster cognitive decline. [Internet]. Cited 2025, September 19. Available from: https://www.aan.com/PressRoom/Home/PressRelease/5281; 4. Gonçalves NG, Martinez-Steele E, Lotufo PA, et al. Association between consumption of low- and no-calorie artificial sweeteners and cognitive decline: An 8-Year prospective study. Neurology. 2025;105(7):e214023. Doi:10.1212/WNL.0000000000214023)