Meta-Analysis of L-carnitine for Metabolic Syndrome

Metabolic syndrome is associated with an increased risk of developing type II diabetes and cardiovascular disease. (2) Metabolic syndrome can described by insulin resistance, impaired glucose tolerance, hypertension, elevated blood lipids, and abdominal obesity.

“L-Carnitine supplementation reduced body weight, body mass index, and fat mass […] [and] was associated with improved fasting blood sugar and insulin resistance […]” (1)

A meta-analysis of randomized controlled trials found that L-carnitine supplements are an effective treatment for influencing biomarkers of metabolic syndrome(1). The results of 9 random, placebo-controlled studies with male and female subjects over 18 years old were analyzed for their outcomes which regard to waist circumference, systolic blood pressure, diastolic blood pressure, fasting blood sugar, triglycerides, and cholesterol.

The most significant results were reduced waist circumference, improved insulin sensitivity and glucose control.

“L-carnitine supplementation can improve glucose metabolism via several mechanisms. First, the enhancement of mitochondrial oxidation of accumulated long-chain acyl-CoA produces insulin resistance in muscle and the heart. Second, it induces changes in glycolytic and gluconeogenic enzymes. Third, it modifies the expression of genes associated with the insulin-signaling cascade. Finally, it improves glucose utilization by the heart” (1)

The study authors concluded that L-carnitine supplementation is correlated with improved biomarkers for Metabolic Syndrome.

1. Choi, M., Park, S., & Lee, M. (2020). L-Carnitine’s Effect on the Biomarkers of Metabolic Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients, 12(9), 2795.

2. Mayo Clinic. (2021). Metabolic Syndrome. Retrieved from: