The Effect of Alpha-Lipoic Acid on Liver Function and Metabolic Markers in Obese Patients with Non-Alcoholic Fatty Liver Disease: A Double - Blind Randomized Controlled Trial

[Background]Insulin resistance has a pivotal role in the occurrence of impaired glucose tolerance and dyslipidemia in patients with Non-Alcoholic Fatty Liver Disease (NAFLD). There is evidence of possible beneficial effects of Alpha-Lipoic Acid (ALA) on insulin resistance and metabolic disorders.[Objectives]This study aimed at examining the effects of ALA supplementation on liver enzymes, insulin sensitivity, glucose markers, and lipid profile in obese patients with NAFLD.[Methods]In this double-blind placebo-controlled randomized clinical trial, 50 obese patients with NAFLD were randomly allocated to “ALA group” (received 1200 mg ALA as two capsules per day) or “Placebo group” (received placebo containing cornstarch as two capsules per day) for 12 weeks. Anthropometric measures, dietary intakes, liver enzymes as well as glucose markers and lipid profile were assessed at baseline and after 12 weeks of intervention.[Results]Forty-five patients completed the study (ALA group = 23; placebo group = 22). Liver enzymes were not significantly altered by the intervention group. Alpha Lipoic Acid supplementation led to a significant attenuation in serum levels of insulin (13.4 ± 5.4 vs. 18.1 ± 8.6; P = 0.019) and triglyceride (146.9 ± 60.6 vs. 186.3 ± 54.2; P = 0.037) in comparison with the placebo group, yet did not affect other lipid profile parameters, Fasting Serum Glucose (FSG) and β-cell function index (HOMA-B) in patients with NAFLD. furthermore, quantitative insulin sensitivity check index (QUICKI) increased significantly in the ALA group compared to the placebo (0.329 ± 0.025 versus 0.317 ± 0.020; P = 0.033).[Conclusions]Patients with NAFLD may benefit from ALA supplementation, at least partially through augmented insulin sensitivity and improvement of lipid profile.