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. Phy tosterol 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 i n 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. Th e study was a randomized, double-blind, placebo-controlled two-period cross -over trial with two treatments and three periods. Both treatment periods l asted 2 months, with a washout period (2 months) between them. Spread enric hed with plant sterols was compared to non-enriched control spread. Fortifi ed fat spread provided 1.6 g/day of plant sterols derived from edible veget able oils and fatty acids from sunflower seed oil. The plant sterol content consisted of sitosterol esters (50%), campesterol esters (25%), stigmaster ol esters (20%) and 10% of other esters. Data in 53 hypercholesterolemic pa tients (31 females and 22 males) who completed the study were as follows: p atients were 58 +/- 12 years of age with mean body mass index 23.5 +/- 2.8 kg/m(2) (mean +/- SD). No adverse side-effects of the diet were reported. P lasma total cholesterol and LDL-C concentrations were significantly reduced by 6.4% and 8.8%, respectively, after using the spread enriched in plant s terols, as compared to controls (0.0% and 1.3%, respectively). No effect on high density lipoprotein-cholesterol (HDL-C) and lipoprotein(a) concentrat ions was detected. When subjects were divided in two subgroups according to fibrate treatment, supplementation with phytosterols decreased plasma chol esterol and LDL-C by 8.5% and 11.1%, respectively in the subgroup of patien ts treated with fibrates. In the group of patients who did not receive fibr ates, consumption of plant sterol margarine reduced plasma cholesterol and LDL-C by 5.5% and 7.7%, respectively. Spread enriched with plant sterol est ers 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 tr eatment and plant sterol ester-supplemented spread offers a safe and effect ive measure to significantly decrease abnormally high cholesterol levels. W e conclude that phytosterol-en rich ed spread is a useful adjunctive therap y for hypercholesterolemic patients.