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.