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.