People with type 2 diabetes may benefit from taking supplements of L-carnitine, a compound made from the amino acids lysine and methionine, new research suggests.
Mariano Malaguarnera and colleagues from the University of Catania in Italy randomly assigned 81 people with type 2 diabetes to receive either 2 grams L-carnitine or a placebo once daily for three months. Results showed that those who had been taking L-carnitine showed significant improvements in several cardiovascular risk factors, compared with participants in the placebo group. Firstly, LDL-cholesterol oxidation dropped by 15.1 units per litre (U/L) of blood, compared to a 3 U/L reduction in the placebo group. Secondly, LDL cholesterol levels dropped by 0.45 mmol/L in the L-carnitine group, whereas levels in the placebo group fell by 0.16 mmol/L. Finally, the thiobarbituric acid-reactive substance (TBARS) assay, a measure of oxidative stress, fell by 1.92 in the L-carnitine group, compared to a reduction of just 0.05 in the placebo group.
The findings led the authors to conclude: “Our study indicates that oral administration of L-carnitine reduces oxidized LDL cholesterol levels in patients with type 2 diabetes,”
Malaguarnera M, Vacante M, Avitabile T, Malaguarnera M, Cammalleri L, Motta M. L-Carnitine supplementation reduces oxidized LDL cholesterol in patients with diabetes. American Journal of Clinical Nutrition. 2009;89:71-76. doi:10.3945/ajcn.2008.26251