Objectives: To study and compare associations of 5 dietary patterns - Mediterranean dietary pattern (MDP), Dietary Approaches to Stop Hypertension (DASH), Mediterranean-DASH Intervention for Neurodegenerative delay (MIND), Alternative Healthy Eating Index (AHEI-2010), and a pro-vegetarian diet (PVD) - with cognitive function. Patients and Methods: A subgroup of 806 participants from the "Seguimiento Universidad de Navarra"(SUN) cohort of university graduates, >55 years old, was interviewed with the validated Spanish Telephone Interview for Cognitive Status (STICS-m) at baseline and after 2 and 6 years. For recruitment to the SUN cohort, participants completed a validated food-frequency questionnaire to calculate dietary adherence scores. These scores were used as independent variables in linear regression models (a model for each dietary pattern) to assess their association with the 6-year change in STICS-m as the dependent variable. Linear mixed models were also fitted to compare trajectories of STICS-m scores. All models were adjusted for relevant confounding factors. Results: Adjusted differences showed advantages in the 6-year change in STICS-m score of 0.25 (95% CI 0.04-0.45) for an increase of 1-SD (9 points) in the AHEI-2010 and of 0.27 (95% CI 0.05-0.48) for an increase of 1-SD (1.5 points) in the MIND diet. The MDP, DASH, and PVD scores yielded positive differences in their point estimates for an increase in 1-SD, but results were not statistically significant. The MIND diet appeared to modify changes in cognitive function over time. Conclusions: Our results showed a beneficial association between the MIND diet and cognitive function and suggested a benefit for the AHEI-2010 pattern. Results for the MDP, DASH, and PVD were inconclusive.