Lack of effect of sugar cane and sunflower seed policosanols on plasma cholesterol in rabbits.

OBJECTIVE: To evaluate the potential for a mixture of policosanol extracted from sunflower oil (SFP) to lower blood cholesterol levels in comparison to sugar cane policosanol (SCP) in rabbits. DESIGN: Twenty three Semi-lop rabbits were blocked into three groups matched on fasting plasma cholesterol levels then randomly assigned to one of three parallel treatment arms: Control (Vehicle 28.6% sunflower oil/70% water/1.4% emulsifier) n = 7; SFP, 100 mg/kg in vehicle, n = 8; SCP, 100 mg/kg in vehicle, n = 8. Rabbits were gavaged once every two days for four weeks. Blood was collected and analysed for plasma lipids. RESULTS: Total cholesterol, non-HDL and HDL cholesterol increased significantly following SCP supplementation relative to the control. SFP supplementation had no effect. Triglyceride levels decreased significantly following all dietary treatments (P < 0.05), possibly due to the emulsifier. CONCLUSION: Dietary supplementation of normocholesterolemic rabbits with policosanol from sunflower oil does not appear to have any cholesterol lowering effect. A similar lack of efficacy observed with the commercial SCP product which we evaluated raises doubts about the purported cholesterol-lowering efficacy of these products, as reflected in the current literature.