Oxidative Stress Responses to Nigella sativa Oil Concurrent with a Low-Calorie Diet in Obese Women: A Randomized, Double-Blind Controlled Clinical Trial

The aim of the present study was to determine the effects of Nigella sativa (NS) oil concurrent with a low-calorie diet on lipid peroxidation and oxidative status in obese women. In this double-blind placebo-controlled randomized clinical trial, 50 volunteer obese (body mass index=30-35 kg/m(2)) women aged 25-50 years old were recruited. Participants were randomly divided into intervention (n=25) and placebo (n=25) groups. They received a low-calorie diet with 3 g/day NS oil or low-calorie diet with 3 g/day placebo for 8 weeks. Forty-nine women (intervention group=25; placebo group=24) completed the trial. NS oil concurrent with a low-calorie diet decreased weight in the NS group compared to the placebo group (-4.80 +/- 1.50 vs. -1.40 +/- 1.90 kg; p<0.01). Comparison of red blood cell superoxidase dismutase (SOD) indicated significant changes in the NS group compared to the placebo group at the end of the study (88.98 +/- 87.46 vs. -3.30 +/- 109.80 U/gHb; p<0.01). But no significant changes in lipid peroxidation, glutathione peroxidase, and total antioxidant capacity concentrations were observed. NS oil concurrent with a low-calorie diet decreased weight and increased SOD levels in obese women. However, more studies are suggested to confirm the positive effects of NS in obesity and its complications. Copyright (C) 2015 John Wiley & Sons, Ltd.