Efficacy of l-carnitine supplementation for management of blood lipids: A systematic review and dose-response meta-analysis of randomized controlled trials.

TLDR: In this article, a systematic review and meta-analysis was conducted to evaluate the efficacy of l -carnitine supplementation on lipid profiles, and the results showed that l-carnitriou supplementation significantly reduced total cholesterol (TC) (56 arms-MD: −8.53 ǫmg/dl, 95% CI: −13.46, −3.6, I2: 93), low-density lipoprotein-cholesterol (LDL-C), and triglyceride (TG), and increased HDL-C (TG) (51

Abstract: Background and aim l -carnitine has an important role in fatty acid metabolism and could therefore act as an adjuvant agent in the improvement of dyslipidemia. The purpose of present systematic review and meta-analysis was to critically assess the efficacy of l -carnitine supplementation on lipid profiles. Methods and results We performed a systematic search of all available randomized controlled trials (RCTs) in the following databases: Scopus, PubMed, ISI Web of Science, The Cochrane Library. Mean difference (MD) of any effect was calculated using a random-effects model. In total, there were 55 eligible RCTs included with 58 arms, and meta-analysis revealed that l -carnitine supplementation significantly reduced total cholesterol (TC) (56 arms-MD: −8.53 mg/dl, 95% CI: −13.46, −3.6, I2: 93%), low-density lipoprotein-cholesterol (LDL-C) (47 arms-MD: −5.48 mg/dl, 95% CI: −8.49, −2.47, I2: 94.5) and triglyceride (TG) (56 arms-MD: −9.44 mg/dl, 95% CI: −16.02, −2.87, I2: 91.8). It also increased high density lipoprotein-cholesterol (HDL-C) (51 arms-MD:1.64 mg/dl, 95% CI:0.54, 2.75, I2: 92.2). l -carnitine supplementation reduced TC in non-linear fashion based on dosage (r = 21.11). Meta-regression analysis indicated a linear relationship between dose of l -carnitine and absolute change in TC (p = 0.029) and LDL-C (p = 0.013). Subgroup analyses showed that l -carnitine supplementation did not change TC, LDL-C and TG in patients under hemodialysis treatment. Intravenous l -carnitine and lower doses (>2 g/day) had no effect on TC, LDL-C and triglycerides. Conclusion l -carnitine supplementation at doses above 2 g/d has favorable effects on patients' lipid profiles, but is modulated on participant health and route of administration.