Exposure and effectiveness of phytosterol/-stanol-enriched margarines

Background: Studies on effectiveness of phytosterol/-stanol-enriched margarines in the community have received low priority. For postlaunch monitoring purposes including risk-benefit analyses, it is needed to investigate both exposure and effectiveness of these margarines. Objective: To study the use and effectiveness of phytosterol/-stanol-enriched margarine. Design, setting and subjects: The study population consisted of 2379 subjects that participated in a community intervention study ('Hartslag Limburg') aged 28-76 years. In 1998 and 2003, blood samples for total and high- density lipoprotein (HDL) cholesterol were obtained. A general questionnaire and food frequency questionnaire (FFQ) were administered. From 1999 onwards, phytosterol/-stanol-enriched margarines were introduced on the Dutch market. On the basis of 2003 data, subjects were classified in users of (a) phytosterol/-stanol-enriched margarine, (b) cholesterol-lowering drugs, (c) the combination (both enriched margarine and drugs) and (d) neither enriched margarines nor cholesterol-lowering drugs. Results: Mean (+/- s.d.) daily intake of phytosterol-enriched margarine (n=99) and phytostanol-enriched margarine (n=16) was 14 +/- 9 g. From 1998 to 2003, total serum cholesterol concentration changed significantly different among the four groups: in the combination users -2.04 +/- 1.50 mmol/l (-29%), in cholesterol-lowering drug users -1.09 +/- 1.17 mmol/l (-17%), in the enriched margarine users -0.24 +/- 0.75 mmol/l (-4%) and in non-users +0.10 +/- 0.72 mmol/l (+2%)(P < 0.05). Conclusion: Recommended doses are not consumed, but phytosterol/-stanol-enriched margarines can modestly reduce serum total cholesterol in the community. These margarines cannot equal the effect of cholesterol-lowering drugs, but may act additively. Further investigation of the health effects that may occur during simultaneous cholesterol lowering drugs and phytosterol-or -stanol-enriched margarines usage is important, as well as community education about the cholesterol lowering foods and drugs. Sponsorship: Netherlands Organization for Health Research and Development (ZonMW) (data collection of Hartslag Limburg and further data-analyses).