Effect of plant sterols in combination with other cholesterol-lowering foods

The National Cholesterol Education Program Adult Treatment Panel III guidelines advocate effective combinations of cholesterol-lowering dietary components. This approach (dietary portfolio) produces large reductions in serum cholesterol, but the contribution of individual components remains to be established. We therefore assessed the effect of eliminating one out of the 4 dietary portfolio components. Plant sterols were selected because at 2 g/d, they have been reported to reduce low-density lipoprotein cholesterol (LDL-C) by 9% to 14%. Forty-two hyperlipidemic subjects were prescribed diets high in soy protein (22.5 g/1000 kcal), viscous fibers (10 g/1000 kcal), and almonds (23 g/1000 kcal) for 80 weeks. Subjects were instructed to take these together with plant sterols (1.0 g/1000 kcal) except between weeks 52 and 62. While taking the full dietary portfolio, including plant sterols, mean LDL-C reduction from baseline was 15.4% +/- 1.6% (P < .001). After sterol elimination, mean LDL-C reduction was 9.0% +/- 1.5% (P < .001). Comparable LDL-C reductions were also seen for the 18 subjects with a complete data set: on plant sterols, 16.7% +/- 3.1% (P < .001) and off plant sterols, 10.3% +/- 2.6% (P < .001), resulting in a 6.3% +/- 2.0% (P = .005) difference attributable to plant sterols. Compliance in this group of 18 was 67.0% +/- 5.9% for plant sterols and 61.9% +/- 4.8% for the other components. In combination with other cholesterol-lowering foods and against the background of a low-saturated fat diet, plant sterols contributed over one third of the LDL-C reduction seen with the dietary portfolio after 1 year of following dietary advice.