Examining the Moderating Role of a Mediterranean Diet in the Relationship Between Perceived Stress and Cognitive Function in Older Adults

Abstract Objectives Perceived stress and adherence to a Mediterranean diet pattern have been identified as independent predictors of cognitive function in older adulthood; however, no studies to date have examined the interaction between perceived stress and diet adherence on cognitive health. This cross-sectional study investigated the synergistic effect of perceived stress and adherence to a Mediterranean diet pattern on cognitive function in 192 nondemented older adults aged 60–95 years. Method Participants completed a Food Frequency Questionnaire (FFQ) and the Perceived Stress Scale (PSS-10). Executive functioning was assessed using the Trail Making Test-Part B (TMT-B) and episodic memory was assessed using the immediate and delayed free recall subscales from the California Verbal Learning Test (CVLT-II). Results Moderation analyses revealed that higher perceived stress was associated with worse executive functioning at low levels of Mediterranean diet adherence (B = 1.75, SE = 0.67, p = .009), but not at moderate and high levels of Mediterranean diet adherence (ps > .05). Perceived stress was not associated with episodic memory, irrespective of Mediterranean diet adherence. Discussion Findings provide preliminary evidence that the association between higher perceived stress and poorer executive function may be dependent on diet intake. Additional research is needed to confirm these findings.