Long-term Adherence and Changes in the Mediterranean and MIND Diets in Relation to Dementia Risk and Cognitive Function.

INTRODUCTION:Associations of adherence to and changes in Mediterranean (MedDiet) and Mediterranean-Dietary Approaches to Stop Hypertension Intervention for Neurodegenerative Delay (MIND) diets with cognitive outcomes are unclear. METHODS:We prospectively followed 86,740 women (Nurses' Health Study, 1980-2023) and 43,500 men (Health Professionals Follow-Up Study, 1986-2023). Diet was assessed repeatedly using food frequency questionnaires. Dementia cases were identified from self-reported physician diagnoses and death records. Cognitive function was assessed by telephone tests, and subjective cognitive decline (SCD) was self-reported. RESULTS:Participants in the highest versus lowest MedDiet and MIND categories had 21% (hazard ratio [HR] = 0.79, 95% confidence interval [CI]: 0.73-0.84) and 14% (HR = 0.86, 95% CI: 0.81-0.91) lower dementia risk, respectively. Higher adherence was associated with 0.75 to 1.59 fewer years of cognitive aging, and 40% to 42% lower risk of SCD. Similar inverse associations were observed for improved adherence over 4 or 8 years. DISCUSSION:Adherence to Mediterranean and MIND diets was associated with cognitive benefits.