Plant sterol-enriched margarine lowers plasma LDL in hyperlipidemic subjects with low cholesterol intake: effect of fibrate treatment.

Phytosterols, found in fat-soluble fractions of plants, chemically resemble cholesterol and inhibit cholesterol absorption in the small intestine. Phytosterol consumption in human subjects reduces plasma total and low density lipoprotein-cholesterol (LDL-C) levels. The primary aim of this study was to determine the efficacy of a low-fat spread enriched with plant sterols in reducing total and LDL-C concentrations in primary hypercholesterolemia. The secondary objective was to evaluate whether patients receiving a lipid-lowering drug (fibrate) might differ in their response to plant sterols. The study was a randomized, double-blind, placebo-controlled two-period cross-over trial with two treatments and three periods. Both treatment periods lasted 2 months, with a washout period (2 months) between them. Spread enriched with plant sterols was compared to non-enriched control spread. Fortified fat spread provided 1.6 g/day of plant sterols derived from edible vegetable oils and fatty acids from sunflower seed oil. The plant sterol content consisted of sitosterol esters (50%), campesterol esters (25%), stigmasterol esters (20%) and 10% of other esters. Data in 53 hypercholesterolemic patients (31 females and 22 males) who completed the study were as follows: patients were 58+/-12 years of age with mean body mass index 23.5+/-2.8 kg/m2 (mean+/-SD). No adverse side-effects of the diet were reported. Plasma total cholesterol and LDL-C concentrations were significantly reduced by 6.4% and 8.8%, respectively, after using the spread enriched in plant sterols, as compared to controls (0.0% and 1.3%, respectively). No effect on high density lipoprotein-cholesterol (HDL-C) and lipoprotein(a) concentrations was detected. When subjects were divided in two subgroups according to fibrate treatment, supplementation with phytosterols decreased plasma cholesterol and LDL-C by 8.5% and 11.1%, respectively in the subgroup of patients treated with fibrates. In the group of patients who did not receive fibrates, consumption of plant sterol margarine reduced plasma cholesterol and LDL-C by 5.5% and 7.7%, respectively. Spread enriched with plant sterol esters significantly lowers blood total and LDL-C levels without affecting HDL-C concentrations, in a hypercholesterolemic population following a strict low cholesterol diet (NCEP step1). In addition, a combination of fibrate treatment and plant sterol ester-supplemented spread offers a safe and effective measure to significantly decrease abnormally high cholesterol levels. We conclude that phytosterol-enriched spread is a useful adjunctive therapy for hypercholesterolemic patients.