The effects of tocotrienol supplementation on lipid profile: A meta-analysis of randomized controlled trials

Abstract

Background & objective: Tocotrienol supplementation has been emerged as a potent candidate for the treatment of dyslipidemia. In the present study, a systematic review and meta-analysis of randomized controlled trials was performed with the aim of examining the effects of tocotrienol supplementation on the lipid profile.

Methods: Four databases (Scopus, PubMed/Medline, Web of Science and Embase) were used to accomplish the literature search up to November 2019. Clinical trials encompassing the impact of tocotrienol supplementation on lipid profile were extracted regardless of clinical condition, with studies included involving only adults patients.

Results: A total of 15 articles with 20 arms were eligible and included in the meta-analysis to estimate the pooled effect size. Overall results showed a significant effect of tocotrienol supplementation on increasing high-density lipoprotein cholesterol (HDL-C) levels (weight mean difference (WMD): 0.146 mmol/L, I² = 85.9%) and a non-significant influence on total cholesterol (TC) (WMD: 0.010 mmol/L, I² = 64.5%), low-density lipoprotein cholesterol (LDL-C) (WMD: 0.095 mmol/L, I² = 87.4%), and triglycerides (TG) (WMD: -0.112 mmol/L, I² = 67.4%) levels. Increment in HDL-C levels was significant greater for the tocotrienol dosage ≥ 200 mg/d (WMD: 0.202 mmol/L) and ≤8 weeks (WMD: 0.278 mmol/L). Moreover, studies that investigated tocotrienol dose ≥200 mg had no heterogeneity, while showing a significant decrease in TG levels (WMD: -0.177 mmol/L).

Conclusion: The present meta-analysis demonstrated that supplementing with tocotrienols does not decrease the concentrations of LDL-C, TC and TG. However, tocotrienol supplementation was considered a candidate for increasing HDL-C levels.

Keywords: HDL; LDL; Lipid profile; Meta-analysis; Tocotrienol; Triglycerides.