Astaxanthin supplementation mildly reduced oxidative stress and inflammation biomarkers: a systematic review and meta-analysis of randomized controlled trials

Previous in vitro and animal studies showed that astaxanthin improved oxidative stress and inflammation biomarkers. We hypothesized the same effects of astaxanthin in humans and conducted a systematic review and meta-analysis of previous randomized controlled trials to test this hypothesis. The literature search was performed on PubMed, Cochrane Library, and Scopus databases from January 1970 to April 2021. Main eligibility criteria include: intervention using astaxanthin for at least 1 week; inclusion of placebo control; and measuring at least 1 of the common oxidative stress and inflammation biomarkers before and after intervention. Twelve randomized controlled trials including 380 participants were included. Compared with placebo, astaxanthin significantly reduced blood malondialdehyde concentration (standardized mean difference [SMD]: -0.95; 95% CI, -1.67 to -0.23; P = .01). The lowering effect of astaxanthin supplementation on malondialdehyde was particularly significant in type 2 diabetes mellitus (T2DM) patients (SMD: -0.64; 95% CI, -1.26 to -0.01; P < .05). A limited number of trials were available for the effects of astaxanthin on other oxidative stress biomarkers. Astaxanthin supplementation appeared to improve superoxide dismutase activity and reduce serum isoprostane concentration in overweight subjects. Astaxanthin significantly reduced blood interleukin-6 concentration in T2DM patients (weighted mean difference: -0.70 pg/mL; 95% CI, -1.29 to -0.11 pg/mL; P = .02). The effects of astaxanthin on blood C-reactive protein and tumor necrosis factor-α concentrations were not significant. The current work indicated that astaxanthin supplementation may be beneficial for improving oxidative stress and certain inflammation biomarkers, particularly in T2DM patients. Future work should investigate the effects of astaxanthin on T2DM.