Association between dietary spermidine intake and cognitive performance in older adults: The U.S. National Health and Nutrition Examination Survey, 2011-2014.

Background: This study aimed to investigate the association between dietary spermidine (SPD) intake and cognitive performance in older adults.

Methods: We analyzed data from the 2011-2014 U.S. National Health and Nutrition Examination Survey (NHANES), including 2674 individuals aged 60 and above. Dietary SPD intake was assessed from 11 specific food sources and total dietary sources. Cognitive function was evaluated through the Immediate Recall Test (IRT), Delayed Recall Test (DRT), Animal Fluency Test (AFT), and Digit Symbol Substitution Test (DSST). A composite Z-score was used to represent overall cognitive performance. Multivariable logistic regression analysis was performed to explore the association between SPD intake and cognitive performance.

Results: Higher SPD intake (highest quartile) was significantly associated with better cognitive performance across all cognitive tests (IRT: OR = 0.72, 95 % CI = 0.55-0.94; DRT: OR = 0.72, 95 % CI = 0.56-0.92; AFT: OR = 0.59, 95 % CI = 0.45-0.76; DSST: OR = 0.50, 95 % CI = 0.37-0.67; Z-score: OR = 0.48, 95 % CI = 0.36-0.64). Subgroup analysis revealed that the protective effect of SPD on cognitive function was more pronounced in males, non-Hispanic whites, individuals with a BMI between 25 and 30 kg/m, and those with hypertension or hyperlipidemia.

Conclusions: This study provides evidence supporting the association between higher dietary SPD intake and improved cognitive performance in older adults. The protective effect was more pronounced in certain subgroups, particularly in males, non-Hispanic whites, and individuals with specific chronic conditions. These findings suggest that SPD may be a valuable component in dietary strategies aimed at improving cognitive health in older adults and populations with chronic diseases.