Low density lipoprotein-cholesterol lowering mechanism and blood lipid profile managing effect of phytosterol in healthy normal and hypercholesterolemia: a meta-analysis of randomly controlled trials / 中华临床营养杂志

ABSTRACT

Objective To investigate the possible mechanism of phytosterol reducing low density lipoprotein cholesterol (LDL-C) in the serum,and evaluate the clinical effect of phytosterol-enriched functional food and dietary supplement on blood lipid profile.Methods We systematically reviewed the literature on the mechanism of phytosterol reducing LDL-C in the serum,and conducted a meta-analysis of randomly controlled trials (RCT) on the clinical effect of phytosterol-enriched functional food and dietary supplement on blood lipid profile.We searched in databases,including PubMed,EMBASE and Cochrane Library,for literature in the timeframe between January 2007 and January 2017,and conducted manual searching and reference review.Researches were strictly screened based on predetermined inclusion and exclusion criteria,and RCTs included in the meta-analysis were tested using the Cochrane Collaboration's tool for assessing risk of bias.The meta-analysis was conducted with RevMan 5.3 to investigate the effects of phytosterol-enriched functional food and dietary supplement on the levels of LDL-C,high density lipoprotein cholesterol (HDL-C) and triglyceride (TG) in the serum of health population and patients with hypercholesterolemia.Results A total of 58 researches were included,of which 46 were related to the cholesterol lowering mechanism of phytosterol and 12 were RCTs on its cholesterol lowering effect.The meta-analysis involved 872 subjects and showed that,in both healthy population and patients with hypercholesteromia,phytosterol-enriched foods and supplements could reduce serum LDL-C level (MD=-0.24,95％ CI=-0.31-0.16,P＜0.000 01) but not HDL-C (MD=0.04,95％ CI=-0.01-0.08,P=0.12) orTG level (MD=0.05,95％ CI=-0.04-0.13,P=0.30).Conclusions Phytosterol-enriched foods and supplements could reduce serum LDL-C level without affecting HDL-C and TG level in both healthy population and patients with hypercholesteromia.Competitive inhibition of cholesterol from entering micelle is one of the established mechanisms behind the LDL-C lowering effect of phytosterol.