Pharmacotherapy Original research| Volume 34, ISSUE 8, P1674-1682, August 2012

Effect of Lysine, Vitamin B6, and Carnitine Supplementation on the Lipid Profile of Male Patients With Hypertriglyceridemia: A 12-Week, Open-Label, Randomized, Placebo-Controlled Trial



      Fat metabolism is known to be altered in hypertriglyceridemia. Fat oxidation requires carnitine, which can be obtained either from the diet (animal or dairy products) or through synthesis in the body using both lysine and vitamin B6.


      The goal of this study was to investigate the effect of lysine, vitamin B6, and carnitine supplementation on both glycemia and the lipid profiles, specifically triglyceride (TG) levels, in men with hypertriglyceridemia.


      This 12-week, randomized, placebo-controlled clinical trial was conducted at a Lebanese medical center. A total of 85 hypertriglyceridemic (TG> 150 mg/dL) male patients were randomized to 1 of 5 groups and given supplements of lysine (1 g/d), vitamin B6 (50 mg/d), lysine (1 g/d) + vitamin B6 (50 mg/d), carnitine (1 g/d), or placebo for 12 weeks. The lipid profile (TG, total cholesterol, LDL-C, and HDL-C) and fasting plasma glucose levels were assessed at baseline and at 6 and 12 weeks.


      Adults (∼50 years) Lebanese males from a low socioeconomic status in Beirut were given the appropriate supplements. Vitamin B6 supplementation was associated with a significant reduction in total cholesterol and HDL-C of ∼10%. In addition, plasma TG was reduced by 36.6 mg/dL at 6 weeks, whereas levels in the placebo group increased by 18 mg/dL; this difference failed to reach statistical significance. No major changes in the lipid profile were observed in the lysine and carnitine groups or when lysine was added to vitamin B6.


      Vitamin B6 supplementation in these male patients with hypertriglyceridemia reduced plasma total cholesterol and HDL-C concentrations.

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