Association of Nut Consumption with Dementia and Alzheimer’s Disease

Background: Nut consumption reduces risks of cardiovascular disease, respiratory disease and depression. However, its association with dementia and Alzheimer’s disease (AD) remains unclear. Methods: A population-based case–control study was conducted in China, including 466 participants aged 52–100 years (233 with dementia). Data on socio-demographic characteristics, lifestyle factors, comorbidities, and dietary intake over the past two years were collected through structured face-to-face interviews. Nut consumption was categorised as non-consumption or <monthly, ≥monthly but <weekly, ≥weekly but <daily, daily, and ≥twice daily. Multiple adjusted logistic regression models were employed to examine the association of nut consumption with dementia and AD. Results: Of the 466 participants, 59.0% reported consuming nuts at non-consumption or <monthly, 22.5% monthly, 11.8% weekly, 6.0% daily, and 0.6% ≥ twice daily. Compared with non-consumption or <monthly consumption, the age-adjusted odds ratio (OR) for dementia was 0.31 (95% CI 0.18–0.52) for monthly intake, 0.52 (0.28–0.97) for weekly intake, and 0.32 (0.14–0.72) for daily or higher intake. After further adjustment for gender, education, family income, marital status, smoking, stroke, chronic bronchitis, depression, and other dietary intakes, OR was 0.27 (0.13–0.55) for monthly intake and 0.47 (0.23–0.99) for ≥weekly intake. Among 133 participants with AD, similar associations were observed, with a fully adjusted OR of 0.34 (0.17–0.69) for ≥monthly nut consumption. Conclusions: Higher nut consumption was associated with reduced risks of dementia and AD. Increasing nut intake may represent a potential strategy for dementia and AD prevention. However, large-scale cohort and interventional studies are needed to further clarify the association and determine the magnitude of the effect.