Effect of citrus flavonoids and tocotrienols on serum cholesterol levels in hypercholesterolemic subjects

Abstract

Context: Preliminary studies have suggested that both citrus flavonoids and palm tocotrienols reduce cholesterol levels in laboratory animals.

Objective: To examine the effect of these nutrients in combination on blood levels of cholesterol and related cardiovascular disease risk factors.

Design: Two open-label studies and 1 double-blind study are reported.

Setting: Outpatient clinical research setting.

Patients: Three groups (n=10, n=10, n=120) of hypercholesterolemic men and women (cholesterol levels >230 mg/dL) between the ages of 19 and 65 years were recruited.

Intervention: Subjects were randomized to consume either 270 mg citrus flavonoids plus 30 mg tocotrienols (S) or placebo (P) daily for a period of 4 weeks (group 1 [G1] and group 2 [G2]) or 12 weeks (group 3 [G3]).

Main outcome measures: Measurements of fasting levels of blood cholesterol, low-density lipoprotein (LDL), high-density lipoprotein (HDL), and triglycerides were made at baseline and 4 weeks (all groups) and at 8 weeks and 12 weeks (G3).

Results: Daily treatment with S significantly improved cardiovascular parameters compared to P in all groups. Significant reductions were shown in total cholesterol (20%-30%), LDL (19%-27%), apolipoprotein B (21%), and triglycerides (24%-34%). HDL levels remained unchanged in G1 and G2 but increased 4% (nonsignificant) in G3 and was accompanied by a significant increase in apolipoprotein A1 (5%).