The effects of low cholesterol, high polyunsaturated fat, and low fat diets on plasma lipid and lipoprotein cholesterol levels in normal and hypercholesterolemic subjects.

The effects of various cholesterol-lowering diets on plasma lipid and hipoprotein cholesterol levels were assessed in normal and hypercholesterolemic subjects. The base-line diet was an ad hibitum hospital diet ofnormah composition. Diet A was a 20% protein, 40% carbohydrate, 40% fat, polyunsaturated:saturated fat ratio 0. 1 to 0.3, 250 to 300 mg cholesterol diet, diet B was identical to diet A except that the polyunsaturated/saturated fat ratio was 1.8 to 2.2, and diet C was a 20% protein, 80% carbohydrate, very low fat (5 to 10 g), polyunsaturated/saturated fat ratio 0.1 to 0.3, 150 to 200 mg cholesterol diet. Diet A (low cholesterol) caused mean reductions in plasma, low-density hipoprotein (LDL), and high-density lipoprotein (HDL) cholesterol of 5.9, 5.6, and 6.3%, respectively, in I I normal subjects. Diet B (low cholesterol, high polyunsaturated fat) caused significant decreases in plasma cholesterol, LDL cholesterol and HDL cholesterol of 17.0, 16.2, and 17.4%, respectively, in 12 normal subjects; and reductions of 1 1.0, 10.8, and 17.1%, respectively, in 19 hyperchohesterolemic subjects. Diet C (low cholesterol, very how fat) produced significant mean decreases in plasma, LDL, and HDL cholesterol of26.7, 29.9, and 27.9%, respectively, in 1 1 normal subjects, and in nine hypercholesterolemic patients of 22.6, 27.2, and 28.6%, respectively. The reductions in plasma cholesterol caused by these diets were therefore due to decreases in both LDL and HDL cholesterol with no significant changes in the LDL cholesteroh:HDL cholesterol ratio. Am. J.Clin.Nutr. 34: 1758-1763, 1981.