Are Supplementation of Omega-3 and Ascorbic Acid Effective in Reducing Oxidative Stress and Depression among Depressed Shift Workers?

Background: This study assessed the effect of supplementation of omega-3 fatty acids and ascorbic acid alone and in combination on the level of lipid peroxidation (malondialdehyde, MDA concentration), total antioxidant capacity (TAC) and depression scores in depressed rotational shift workers in the Tehran Shahid Tondgoyan Oil refinery. Material and methods: In this randomized, double-blind, placebo-controlled trial, 136 men who met the inclusion and exclusion criteria and had a Beck Depression Inventory (BDI) score >= 10 were selected. Among the participants, 33 received omega-3 fatty acid soft gel (1000 mg twice daily) with vitamin C (250 mg twice daily) (group 1), 31 took omega-3 fatty acid supplements and vitamin C placebo (group 2), 30 took omega-3 fatty acid supplement placebo and vitamin C (group 3), and 32 received omega-3 fatty acid supplement placebo and vitamin C placebo (group 4) for 2 months. Measured were serum MDA, TAC concentrations, and BDI scores at baseline and after 2 months. Results: This study showed that the BDI score was reduced significantly in all 4 groups, however, the level of decrease was more in the omega-3 fatty acid (alone) supplementation group (mean 6.29 score decrease) (p < 0.001). MDA level decreased significantly in groups with omega-3 fatty acids (mean 0.78 mu mol/L +/- 1.64 mu mol/L decrease) (p = 0.014) or vitamin C supplementation alone (mean 0.74 mu mol/L +/- 1.55 mu mol/L decrease) (p = 0.014), but not in combination. Conclusions: Supplementation of omega-3 fatty acids alone and not in combination with vitamin C had a better impact on depression and MDA level pronounced in depressed male shift workers.