Evaluation of the relationship between adherence to Mediterranean diet and dietary inflammatory index and cognitive flexibility in emerging adults

The primary aim of this study was to examine the impact of dietary habits and the Dietary Inflammatory Index (DII) on cognitive flexibility (CF) emerging adults (EAs). 415 EAs aged 18–24 years enrolled and data encompassing demographic and anthropometric measurements, adherence to the Mediterranean Diet (MD) was assessed using the KIDMED index, while CF was measured via the Cognitive Flexibility Inventory (CFI). The DII was evaluated based on a 24-h dietary recall intake record. Logistic regression models were used to examine the relationship between DII and CFI, dichotomized by its median value. The analysis included a non-adjusted model, Model 1 adjusted for age and sex, and Model 2 further adjusted for adherence to the MD and BMI. There was a significant difference in mean DII scores across DII quartiles (p = 0.001), while CFI scores did not show any significant differences (p = 0.175). A significant variation was observed in DII score among DII groups (p = 0.026). In non-adjusted model, for every one-point increase in the DII, the odds ratio (OR) is − 0.947, with a p-value of 0.030, indicating an inverse association between DII and CFI. When analysing DII categorically, individuals in higher Q2–Q4 show increasingly higher odds ratios compared to the reference group (Q1), with Q4 displaying the most substantial OR at 3.540 [95% CI 1.195–6.283]. Findings showed a pro-inflammatory diet is associated with an increased risk of cognitive inflexibility. This underscores the need for targeted interventions to enhance the anti-inflammatory qualities of diets, to improve CF among this EA.