ABSTRACT
BACKGROUND: Fluid intelligence (FI) involves abstract problem-solving without prior knowledge. Greater age-related FI decline increases Alzheimer's disease (AD) risk, and recent studies suggest that certain dietary regimens may influence rates of decline. However, it is uncertain how long-term food consumption affects FI among adults with or without familial history of AD (FH) or APOE4 (É4). OBJECTIVE: Observe how the total diet is associated with long-term cognition among mid- to late-life populations at-risk and not-at-risk for AD. METHODS: Among 1,787 mid-to-late-aged adult UK Biobank participants, 10-year FI trajectories were modeled and regressed onto the total diet based on self-reported intake of 49 whole foods from a Food Frequency Questionnaire (FFQ). RESULTS: Daily cheese intake strongly predicted better FIT scores over time (FH-: ß=â0.207, pâ<â0.001; É4-: ß=â0.073, pâ=â0.008; É4+: ß=â0.162, pâ=â0.001). Alcohol of any type daily also appeared beneficial (É4+: ß=â0.101, pâ=â0.022) and red wine was sometimes additionally protective (FH+: ß=â0.100, pâ=â0.014; É4-: ß=â0.59, pâ=â0.039). Consuming lamb weekly was associated with improved outcomes (FH-: ß=â0.066, pâ=â0.008; É4+: ß=â0.097, pâ=â0.044). Among at risk groups, added salt correlated with decreased performance (FH+: ß=â-0.114, pâ=â0.004; É4+: ß=â-0.121, pâ=â0.009). CONCLUSION: Modifying meal plans may help minimize cognitive decline. We observed that added salt may put at-risk individuals at greater risk, but did not observe similar interactions among FH- and AD- individuals. Observations further suggest in risk status-dependent manners that adding cheese and red wine to the diet daily, and lamb on a weekly basis, may also improve long-term cognitive outcomes.