Effect of fatty and lean fish intake on lipoprotein subclasses in subjects with coronary heart disease: a controlled trial

BACKGROUND: Fish oil intake reduces serum triglycerides; however, little is known about the effects of dietary fish intake on lipoprotein subclasses. OBJECTIVE: We aimed at assessing the effect of fatty and lean fish intake on the lipoprotein subclasses in an intervention study. METHODS: The intervention study included 33 patients with coronary heart disease, who were aged 61.0 ± 5.8 (mean ± SD) years. The subjects were randomly assigned to a fatty fish (n = 11), lean fish (n = 12), or control (n = 10) diet for 8 weeks. Fish diets included at least 4 fish meals per week. Subjects in the control group consumed lean beef, pork, and chicken. Lipoprotein subclasses and their lipid components were determined by nuclear magnetic resonance spectroscopy. RESULTS: Concentrations of n-3 fatty acids and docosahexaenoic acid increased in the fatty fish group. The concentrations of cholesterol, cholesterol esters, and total lipids in very large high-density lipoproteins (HDLs) increased in the fatty fish group (overall difference P = .005, P = .002, and P = .007, respectively; false discovery rate P = .04, P = .04, and P = .05, respectively). The mean size of HDL particles increased in the fatty fish group (9.8 ± 0.3 nm at baseline and 9.9 ± 0.4 nm at end of study; overall difference P = .004, false discovery rate P = .04). The fish diets did not affect very-low-density lipoprotein or low-density lipoprotein size. CONCLUSION: Fatty fish intake at least 4 times per week increases HDL particle size which might have beneficial effect in patients with coronary heart disease.