Differential relationship between dietary fat and cholesterol on total mortality in Korean population cohorts

Abstract

Background: Associations among dietary fat, cholesterol intake and total mortality remain controversial, and most available data cover Western populations. The aim of this study was to assess associations for dietary fat and cholesterol in relation to total mortality in Koreans.

Methods: This study used data from three prospective Korean Genome and Epidemiology studies (conducted between June 2001 and December 2013). A total of 194,295 middle-aged and older Korean adults were included. Dietary fat intake was classified into quintiles. Dietary cholesterol intake was categorized into three groups based on cholesterol intake as follows: <200 mg, 200-299 mg and ≥300 mg. A multivariable Cox frailty model with random effects was applied to calculate hazard ratios (HR) and 95% confidence intervals (CIs) after adjusting for confounders.

Results: We documented 3866 deaths across a mean (min-max) follow-up period of 8.15 years (3-13 years). Higher fat intake was associated with lower total mortality (Q5 vs. Q1, HR 0.82 [95% CI 0.69, 0.98]; p trend < 0.01) after adjusting for age, sex, body mass index, alcohol, smoking, exercise and total calorie and protein (%) intake. Higher dietary cholesterol intake (≥300 mg/day) was associated with a higher risk of total mortality (HR 1.19 [95% CI 1.04, 1.37]) than lower cholesterol intake (<200 mg/day) in the multivariate model.

Conclusions: In Koreans, high dietary fat intake is associated with a lower risk of total mortality, while dietary cholesterol intake above 300 mg/day is associated with a higher risk of total mortality.