Objective: To explore the association between the intake of sugar-sweetened beverages and cognitive dysfunction in middle-aged and older adults, so as to provide an evidence-based basis for the early prevention of cognitive dysfunction.

Methods: A comprehensive search of relevant literature was conducted in PubMed, EMBase, Cochrane, ScienceDirect, and Web of Science from the inception until January 2021. Odds ratios (OR), hazard ratios (HR) and 95% confidence intervals (CI) were calculated using a random-effects, generic inverse variance method. Meta-analysis of the included studies was performed using Review Manager 5.4.

Results: A total of 10 studies on the association between sugary beverages and cognitive dysfunction in middle-aged and older adults were included, of which 3 were cross-sectional studies and the rest were cohort studies. Eight of the ten studies had results suggestive of a negative association. However, Meta-analysis results showed that the association between the intake of sugar-sweetened beverages and the risk of cognitive impairment was not statistically significant (OR=1.59, 95% CI: 0.93-2.74, P=0.08); but from two studies, the hazard ratios of all-cause dementia in middle-aged and older people consuming sugar-sweetened beverages was 2.77 (95%CI: 2.24-3.43, P<0.00001); the hazard ratios of Alzheimer's disease in middle-aged and older people consuming sugar-sweetened beverages was 2.63 (95%CI: 1.70-4.05, P<0.0001).

Conclusion: There is insufficient evidence to state conclusively that sugar-sweetened beverages intake causes cognitive dysfunction in middle-aged and older adults.