Long-Term Intake of Red Meat in Relation to Dementia Risk and Cognitive Function in US Adults

BACKGROUND AND OBJECTIVES: Previous studies have shown inconsistent associations between red meat intake and cognitive health. Our objective was to examine the association between red meat intake and multiple cognitive outcomes. METHODS: In this prospective cohort study, we included participants free of dementia at baseline from 2 nationwide cohort studies in the United States: the Nurses' Health Study (NHS) and the Health Professionals Follow-Up Study (HPFS). Diets were assessed using a validated semiquantitative food frequency questionnaire. We ascertained incident dementia cases from both NHS participants (1980-2023) and HPFS participants (1986-2023). Objective cognitive function was assessed using the Telephone Interview for Cognitive Status (1995-2008) among a subset of NHS participants. Subjective cognitive decline (SCD) was self-reported by NHS participants (2012, 2014) and HPFS participants (2012, 2016). Cox proportional hazards models, general linear regression, and Poisson regression models were applied to assess the associations between red meat intake and different cognitive outcomes. RESULTS: = 0.04). Replacing 1 serving per day of nuts and legumes for processed red meat was associated with a 19% lower risk of dementia (HR 0.81, 95% CI 0.75-0.86), 1.37 fewer years of cognitive aging (95% CI -2.49 to -0.25), and a 21% lower risk of SCD (RR 0.79, 95% CI 0.68-0.92). DISCUSSION: Higher intake of red meat, particularly processed red meat, was associated with a higher risk of developing dementia and worse cognition. Reducing red meat consumption could be included in dietary guidelines to promote cognitive health. Further research is needed to assess the generalizability of these findings to populations with diverse ethnic backgrounds.