Aim: Present study aimed to elucidate the suppression of serum lipids by gamma-and delta-tocotrienol ( T3).Methods: The lipid-lowering effects of T3 were investigated using HepG2 liver cell line, hypercholesterolemic mice and borderline-high cholesterol patients. Results:In-vitro results demonstrated two modes of action. First, T3 suppressed the upstream regulators of lipid homeostasis genes (DGAT2, APOB100, SREBP1/2 and HMGCR) leading to the suppression of triglycerides, cholesterol and VLDL biosyntheses. Second, T3 enhanced LDL efflux through induction of LDL receptor (LDLr) expression. Treatment of LDLr-deficient mice with 1 mg/day (50 mg/kg/day) T3 for one-month showed 28%, 19% reduction in cholesterol and triglyceride levels respectively, whereas HDL level was unaltered. The lipid-lowering effects were not affected by alpha-tocopherol ( TP). In a placebo-controlled human trial using 120 mg/day T3, only serum triglycerides were lowered by 28% followed by concomitant reduction in the triglyceriderich VLDL and chylomicrons. In contrast, total cholesterol, LDL and HDL remained unchanged in treated and placebo groups. The discrepancies between in-vitro, in-vivo and human studies may be attributed to the differential rates of post-absorptive T3 degradation and LDL metabolism. Conclusion: Reduction in triglycerides synthesis and transport may be the primary benefit caused by ingesting T3 in human.