Abstract

This study examined the effect of plant sterols added, together with an emulsifying agent, to a low-fat yoghurt on the serum lipid and plant sterol values in moderately hypercholesterolaemic volunteers. Study I was a randomized double-blind, cross-over trial. For 4 weeks, 15 volunteers consumed yoghurt containing 1 g plant sterols or a placebo yoghurt. Study II was a randomized, double-blind, parallel-group study. For 8 weeks, the sterol group (n = 12) ingested daily two yoghurts (2 g/day plant sterols) and the placebo group (n = 14) ingested two yoghurts without plant sterols. Study I: compared with the placebo, the sterol yoghurt reduced serum total cholesterol by 0.15 mmol/l (2.2%, P=0.235) and low-density lipoprotein (LDL) cholesterol by 0.19 mmol/l (4.3%, P=0.082), and increased serum campesterol by 0.26 mg/100 ml (P=0.006) and sitosterol by 0.11 mg/100 ml (P=0.015). Study II: compared with the placebo, the sterol yoghurt reduced serum total cholesterol by 0.41 mmol/l (6.3%, P=0.167) and LDL cholesterol by 0.28 mmol/l (6.4%, P=0.306), and increased serum campesterol by 0.28 mg/100 ml (P=0.016) and sitosterol by 0.40 mg/100 ml (P=0.206). Meta-analysis: the pooled treatment difference was -0.34 mmol/l (5.2%, P=0.173) in total cholesterol and was -0.26 mmol/l (-5.8%, P=0.261) in LDL cholesterol, when the sterol yoghurt was compared with the placebo. A low-fat yoghurt enriched with 1-2 g/day plant sterols reduced serum cholesterol levels in moderately hypercholesterolaemic subjects. Campesterol and sitosterol serum levels increased, but their concentration remained in the range of normal values.