Phytosterols supplementation decreases plasma small and dense LDL levels in metabolic syndrome patients on a westernized type diet

Abstract

Background and aims

Several studies have observed a hypocholesterolemic effect of plant sterols in hypercholesterolemic patients on a balanced diet. The aim of this study was to examine the effect of phytosterol supplementation on risk factors of coronary artery disease in metabolic syndrome patients on a Westernized type diet.

Methods and results

In a randomized placebo-controlled design 108 patients with metabolic syndrome were assigned to consume either 2 plant sterol-enriched yogurt mini drink which provided 4 g phytosterols per day, or a yogurt beverage without phytosterols (control). The duration of the study was 2 months and the patients in both groups followed their habitual westernized type diet and recording it on food diaries. Blood samples were drawn at baseline and after 2 months of intervention. After 2 months supplementation with phytosterols, a significant reduction in total cholesterol, LDL-cholesterol, small and dense LDL (sdLDL) levels, as well as, apoB and triglycerides concentrations were observed in the intervention group (P < 0.05) compared to the control group. In addition, phytosterol supplementation lowered serum total cholesterol by 15.9%, LDL-cholesterol by 20.3% and triglyceride levels by 19.1% (P = 0.02, P < 0.001 and P < 0.001, respectively), although the patients kept their habitual westernized type diet. No differences were observed in HDL cholesterol, apoA1, glucose, C-reactive protein, fibrinogen levels and blood pressure.

Conclusions

Phytosterol supplementation improves risk factors of coronary artery disease even if the diet is a westernized type.

Introduction

The metabolic syndrome has become a subject of great interest due to the clustering of several cardiovascular risk factors, elevated plasma levels triglycerides and glucose, low HDL cholesterol, raised blood pressure and obesity. Most people with this syndrome have an atherogenic lipid profile and insulin resistance, which classifies them as a high risk group for cardiovascular disease and type 2 diabetes and thus lifestyle changes are proposed [1]. The new ATPIII guidelines for the treatment of the metabolic syndrome recommended an increase in monounsaturated fatty acids (MUFA) intake, while there is also clear evidence that phytosterols have a hypocholesterolemic effect [2].

Although dyslipidaemia of the metabolic syndrome patients is characterized by elevated triglycerides and/or low HDL-cholesterol, lipid management should be steered, along with LDL-cholesterol goals, according to European guidelines on cardiovascular disease prevention in clinical practice. In terms of nutritional treatment, except for individualized dietetic recommendations, it was clearly suggested that phytosterols may help reduce plasma concentrations of LDL-cholesterol [3].

More recently the European Food Safety Authority (EFSA) approved a health claim for plant sterols, describing them as agents recommended and consumed only by people who want to lower their blood cholesterol. In line with EFSA, a clinically significant LDL-cholesterol effect of about 9% reduction is considered possible and it can be achieved by a daily intake of 2–2.4 g of phytosterols in an appropriate food (e.g. plant sterols added to fat-based foods and low-fat foods such as milk and yoghurt). However, it is suggested that the recommended amounts and patterns of consumption required to lower blood LDL-cholesterol can be achieved as part of a balanced diet [4], [5], [6], [7]. Furthermore, little is known on whether phytosterols have an effect when the background diet is a westernized type, rich in total and saturated fat.

Therefore, the purpose of this study was to examine the effect of phytosterol supplementation on risk factors of coronary artery disease in metabolic syndrome patients, on a westernized type diet.