Introduction: It is unclear whether eating Western diet food components offsets the Mediterranean diet's (MedDiet) potential benefits on cognitive decline.
Methods: The study includes 5001 Chicago Health and Aging Project participants (63% African American, 36% males, 74 ± 6.0 years old), with food frequency questionnaires and ≥ two cognitive assessments over 6.3 ± 2.8 years of follow-up. Mixed-effects models were adjusted for age, sex, education, race, cognitive activities, physical activity, and total calories.
Results: Stratified analysis showed a significant effect of higher MedDiet on cognitive decline only with a low Western diet score (highest vs lowest MedDiet tertile: β = 0.020, P = .002; p trend = 0.002) and not with a high Western diet score (highest vs lowest MedDiet tertile: β = 0.010, P = .11; p trend = 0.09).
Conclusion: This prospective study found that high consumption of Western diet components attenuates benefits of the MedDiet on cognition.
Keywords: Mediterranean diet; Western diet; biracial; high-fat diet; longitudinal.
© 2021 the Alzheimer's Association.