No significant effects of lutein, lycopene or β-carotene supplementation on biological markers of oxidative stress and LDL oxidizability in healthy adult subjects

Objective: The objective of this study was to determine the effect of individual carotenoid supplementation on biochemical indices of oxidative status in apparently healthy adult males. Methods: The study was a placebo controlled single blind study. Healthy male volunteers (n=175) were assigned to four groups. They received daily supplements of beta -carotene (15 mg), lutein (15 mg), lycopene (15 mg) and placebo fur three months. The effects of the supplementation on antioxidant status were monitored by plasma carotenoid, vitamin C and A levels, glutathione (GSH and GSSG) concentrations, protein SH groups. erythrocyte antioxidant enzyme activities (Cu-Zn SOD, Se-GSH-Px) and susceptibility of LDL to copper-induced oxidation. Results: beta -carotene, lycopene and lutein supplementation led to significant plasma and LDL increases in each of these carotenoids, without modifications of other carotenoid levels in plasma or in LDL. The supplementation failed to enhance the resistance of LDL to oxidation or to modify the LDL polyunsnturated/saturated fatty acid ratio. Vitamin C, GSH, protein SH groups and antioxidant metalloenzyme activity are also unchanged. Conclusion: We did not observe beneficial or adverse effects of lutein, lycopene or beta -carotene supplementation on biomarkers of oxidative stress. In apparently healthy subjects, carotenoid supplementation does not lead to significantly measurable improvement in antioxidant defenses.