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

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%).