Effects of synbiotic versus omega-3 supplementation on total antioxidant capacity in adolescents exposed to ambient air pollution: A randomized double-blind controlled trial

Background: Air pollution promotes oxidative stress and may impair antioxidant defense. Synbiotics and omega-3 fatty acids have been suggested to improve antioxidant status; however, comparative evidence in adolescents exposed to air pollution remains limited. This study compared the effects of synbiotic and omega-3 supplementation on total antioxidant capacity (TAC) in healthy adolescents living in polluted environments. Materials and Methods: This randomized, double-blind, active-controlled clinical trial was conducted in Isfahan, Iran, among 70 healthy adolescents aged 10–18 years exposed to ambient air pollution. Participants were randomly assigned to receive either synbiotic supplementation ( n = 38) or omega-3 fatty acids ( n = 32) for 8 weeks. Serum TAC was measured at baseline and postintervention. Data were analyzed using paired t -tests, independent t -tests, and analysis of covariance. Results: TAC increased significantly following the 8-week intervention in both the synbiotic group (839.78 ± 133.80–903.37 ± 111.90 µmol/L, P = 0.005) and the omega-3 group (898.63 ± 86.45–953.28 ± 100.42 µmol/L, P = 0.004). However, no significant difference was observed between the two groups after the intervention ( P = 0.75). Conclusion: Both synbiotic and omega-3 supplementation were associated with significant improvements in TAC among adolescents exposed to ambient air pollution. However, no significant difference was observed between the two interventions, suggesting that synbiotic supplementation was not superior to omega-3 in enhancing antioxidant capacity under the conditions of this study.