Background: Intake of saturated fat, trans fat, and alcohol alter cardiovascular disease risk, but their effect on subclinical atherosclerosis remains understudied.
Objective: The objective was to examine and quantify the interrelation of saturated fat, trans fat, alcohol intake, and mean carotid artery intimal medial thickness (IMT).
Design: We conducted a population-based, cross-sectional study among 620 persons of Aboriginal, South Asian, Chinese, or European origin aged 35-75 y, who had lived in Canada for >or=5 y. Mean IMT was calculated from 6 well-defined segments of the right and left carotid arteries with standardized B-mode ultrasound, and saturated fat, trans fat, and alcohol intakes were measured with validated food-frequency questionnaires.
Results: For every 10-g/d increase in saturated fat intake, IMT was 0.03 mm higher (P=0.01) after multivariate adjustment. A 1-g/d higher intake of trans fat was associated with a 0.03-mm higher IMT (P=0.02) after multivariate adjustment. The ratio of polyunsaturated to saturated fat (P:S) was inversely associated with IMT after multivariate adjustment (change in IMT: -0.06 mm; P<0.01). Saturated and trans fat intakes were independently associated with IMT thickness (change in IMT: 0.03 mm; P<0.01 and 0.02, respectively; P for interaction=0.01). Polyunsaturated, monounsaturated, cholesterol, and total fat intakes were unrelated to IMT. The relation between saturated fat intake and IMT strengthened (beta=0.0066, P<0.001) in persons who never or rarely consumed alcohol as compared with moderate or heavy drinkers (beta=0.0001, P=0.79, P for interaction=0.01).
Conclusion: Higher habitual intakes of saturated and trans fats are independently associated with increased subclinical atherosclerosis, and alcohol intake may attenuate the relation between saturated fat and subclinical atherosclerosis.