ObjectivesWe aimed to examine the association between dietary intakes of fat and risk of cognitive impairment in Chinese adults, which has rarely been evaluated. MethodsThe Singapore Chinese Health Study is an ongoing cohort among Chinese adults living in Singapore. Dietary information was assessed by a validated food-frequency questionnaire at baseline (1993–1998) when the participants were aged 45–74 years old. Cognitive impairment was identified using modified Singapore version of Mini-Mental State Examination at the 3rd follow-up interviews (2014–2016). After a mean follow-up of 19.7 years, 16,948 surviving participants was included in the final analysis. Multivariable logistic regression models were used to calculate odds ratio (OR) and 95% confidence interval (CI) with adjustment for potential confounders. ResultsCognitive impairment was presented in 2443 participants. Compared to total carbohydrate, dietary fat intake was inversely related to cognitive impairment (OR comparing extreme quartiles = 0.82; 95% CI 0.69–0.97; P-trend = 0.008). The OR (95% CI) comparing extreme quartiles of specific dietary fats was 1.08 (0.89–1.31) for saturated fatty acids (SFAs; P-trend = 0.50), 0.81 (0.65–1.00) for monounsaturated fatty acids (MUFAs; P-trend = 0.03), 0.83 (0.71–0.97) for polyunsaturated fatty acids (PUFAs; P-trend < 0.001), 0.92 (0.77–1.10) for n-3 PUFAs (P-trend = 0.49), and 0.83 (0.71–0.99) for n-6 PUFAs (P-trend = 0.01). Plant-based fat showed an inverse association with cognitive impairment (OR 0.84; 95% CI 0.72–0.98; P-trend = 0.02), whereas no significant association was found for animal fat (P-trend = 0.97). When compared to SFAs, inverse associations remained similar for MUFAs (P-trend = 0.03) and PUFAs (P-trend < 0.001). ConclusionsIn this large population-based cohort in Chinese adults, we found that substitution of total carbohydrate or SFAs with MUFAs and PUFAs, mainly n-6 PUFAs, was related to a lower risk of cognitive impairment. Furthermore, plant-based fat intake was associated with a lower risk. Our results indicate the importance of considering the quality of fat intake in preventing cognitive impairment. Funding SourcesNational Medical Research Council, Singapore; National Institutes of Health; National Key Research and Development Program of China. Supporting Tables, Images and/or Graphs▪