In a study involving 30 patients with type 2 diabetes mellitus, intravenous administration of alpha-lipoic acid (ALA) for 3 weeks was found to reduce concentrations of asymmetric dimethylarginine (mean change: -0.05 micromol/L) – which when elevated, is associated with cardiovascular events in patients with type 2 diabetes. No such change was found when placebo was administered (0.01 micromol/L). ALA treatment did not affect levels of symmetric dimethylarginine and L-arginine. The authors conclude, "Long-term studies need to demonstrate if ALA may cause cardiovascular risk reduction."