Consumption of plant stanols and sterols was not associated with adverse effects that were investigated in a total of 28 studies. Seventeen randomized controlled trials (RCTs) demonstrated effective serum cholesterol-lowering benefits without any reported adverse effects, including no significant effect on fat soluble vitamin status. Very limited data suggest otherwise. Two other RCTs reported lowering of carotenoid levels. Although three of six observational studies report a possible association between plasma or tissue sterol levels and increased risk of coronary heart disease (CHD), the short-term RCTs do not indicate negative effects on vascular function.
