Barley, like oats, is a rich source of the soluble fibre β-glucan, which has been shown to significantly lower LDL-cholesterol (LDL-C). However, barley foods have been less widely studied. Therefore, we evaluated the LDL-C-lowering effect of a concentrated barley β-glucan (BBG) extract as a vehicle to deliver this potential health benefit of barley. In a 10-week blinded controlled study, subjects were randomized to one of four treatment groups or control. Treatment groups included either high molecular weight (HMW) or low molecular weight (LMW) BBG at both 3 and 5 g doses. Treatment was delivered twice per day with meals in the form of two functional food products: a ready-to-eat cereal and a reduced-calorie fruit juice beverage. Levels of total cholesterol, LDL-C, HDL-cholesterol (HDL-C), and TAG were determined at baseline and after 6 weeks of treatment. The study group comprised 155 subjects. All treatments were well tolerated and after 6 weeks of treatment the mean LDL-C levels fell by 15 % in the 5 g HMW group, 13 % in the 5 g LMW group and 9 % in both the 3 g/d groups, versus baseline. Similar results were observed for total cholesterol. HDL-C levels were unchanged by treatment. Concentrated BBG significantly improves LDL-C and total cholesterol among moderately dyslipidaemic subjects. Food products containing concentrated BBG should be considered an effective option for improving blood lipids.

Consumption of concentrated barley beta-glucan lowers plasma cholesterol because of its soluble dietary fiber nature. The role of molecular weight (MW) in lowering serum cholesterol is not well established. Prior studies showed that enzymatic degradation of beta-glucan eliminates the cholesterol-lowering activity; however, these studies did not evaluate the MW of the beta-glucan. The current study was conducted to evaluate whether barley beta-glucan concentrates, partially hydrolyzed to reduce MW, possess cholesterol-lowering and antiatherogenic activities. The reduced MW fraction was compared with a high MW beta-glucan concentrate from the same barley flour. Concentrated beta-glucan preparations were evaluated in Syrian Golden F(1)B hamsters fed a hypercholesterolemic diet (HCD) with cholesterol, hydrogenated coconut oil, and cellulose. After 2 wk, hamsters were fed HCD or diets that contained high or reduced MW beta-glucan at a concentration of 8 g/100 g at the expense of cellulose. Decreases in plasma total cholesterol (TC) and non-HDL-cholesterol (non-HDL-C) concentrations occurred in the hamsters fed reduced MW and high MW beta-glucan diets. Plasma HDL-C concentrations did not differ. HCD-fed hamsters had higher plasma triglyceride concentrations. Liver TC, free cholesterol, and cholesterol ester concentrations did not differ. Aortic cholesterol ester concentrations were lower in the reduced MW beta-glucan-fed hamsters. Consumption of either high or reduced MW beta-glucan increased concentrations of fecal total neutral sterols and coprostanol, a cholesterol derivative. Fecal excretion of cholesterol was greater than in HCD-fed hamsters only in those fed the reduced MW beta-glucan. Study results demonstrate that the cholesterol-lowering activity of barley beta-glucan may occur at both lower and higher MW.