Fish oil attenuates the cholesterol induced rise in lipoprotein cholesterol.

Fish oils rich in n-3 fatty acids lower plasma triglyceride profoundly but the effect on plasma cholesterol is not clear. This study tested the capacity of MaxEPA oil to modify the rise in lipoprotein cholesterol during cholesterol-rich diets. Six subjects were tested with three diets: 1) habitual (P/S 0.47, cholesterol 710 mg/d); 2) fish oil (40 g/d MaxEPA, P/S 1.62, cholesterol 190 mg/d); 3) fish oil + egg yolk (P/S 1.62, cholesterol 940 mg/d). Changing from habitual to fish oil significantly lowered cholesterol and triglyceride levels in plasma, VLDL, LDL, and HDL and in plasma apo-A1 and apo-B. However the addition of 750 mg/d cholesterol to the fish oil failed to raise lipoprotein cholesterol or apoprotein levels significantly, although plasma cholesterol rose slightly; n-3 fatty acids are therefore capable of lowering lipoprotein cholesterol even when the intake of cholesterol is high.