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The cholesterol lowering effects of plant sterols and stanols are a well-established complementary means by which to reduce blood cholesterol concentrations. The average reduction in LDL cholesterol concentrations is approximately -10% following a 28-day supplementation protocol. There is very little known regarding what, if any, effect plant sterols and stanols have on other cardiometabolic risk factors such as blood pressure and endothelial function. Here we review the available literature on this topic and attempt to draw conclusions regarding any benefit or risk for blood pressure and endothelial function linked to plant sterol and stanol supplementation. Generally there has been very little work focusing on changes in blood pressure or endothelial function following plant sterol or stanol intervention, but these factors have been measured in some cases as secondary outcomes. Overall, there is little evidence to support either positive or negative effects of plant sterol or stanol supplementation of blood pressure and the data surrounding endothelial function is quite inconclusive. This area of research would benefit from well controlled mechanistic studies in animals and primary interventions in humans which focus on ambulatory blood pressure, central blood pressure and endothelial function. [ABSTRACT FROM AUTHOR]

Phytosterols (PS) have long been recognized for their cholesterol-lowering action, however, recent work has highlighted triglyceride (TG)-lowering responses to PS that may have been overlooked in previous human interventions and mechanistic animal model studies. This review assesses the current state of knowledge regarding the effect of dietary PS supplementation on blood TG concentrations by examining the average therapeutic response, potential mechanisms, and metabolic and genetic factors that may contribute to inter-individual variability. Data from human intervention trials demonstrates that, compared to baseline concentrations, PS supplementation results in a variable TG-lowering response ranging from 0.8 to 28%. It is evident that hypertriglyceridemic individuals (>1.7 mmol/L) have a greater TG-lowering response to PS (11-28%) than subjects with normal plasma TG concentrations (0.8-7%). Although a genetic basis for the variable TG-lowering effects of PS is probable, there are only limited studies to draw on. The available data suggest that polymorphisms in the apolipoprotein E (apoE) gene may affect responsiveness, with PS-induced reductions in TG more readily evident in apoE2 than apoE3 or E4 subjects. Although only a minimal number of animal model studies have been conducted to specifically examine the mechanisms whereby PS may reduce blood TG concentrations, it appears that there may be multiple mechanisms involved including interruption of intestinal fatty acid absorption and modulation of hepatic lipogenesis and very low density lipoprotein packaging and secretion. In summary, the available data suggest that PS may be an effective therapy to lower blood TG, particularly in hypertriglyceridemic individuals. However, before PS can be widely recommended as a TG-lowering therapy, studies that are specifically powered and designed to fully access therapeutic responses and the mechanisms involved are required. [ABSTRACT FROM AUTHOR]