Overall skin tone and skin-lightening-improving effects with oral supplementation of lutein and zeaxanthin isomers: A double-blind, placebo-controlled clinical trial

Abstract

Purpose: Carotenoids, especially lutein and zeaxanthin isomers (L/Zi), filter blue light and protect skin from environmental factors including high-energy sources. These carotenoids may be able to block the formation of melanin pathways, decrease cytokines, and increase antioxidants. Subjects and methods: This is a randomized, double-blind, placebo-controlled clinical trial over a 12-week supplementation period. Fifty healthy people (50 healthy subjects were recruited and 46 subjects completed the study) (males and females, age: 18–45 years) with mild-to-moderate dry skin were included in this study. Skin type of the subjects was classified as Fitzpatrick skin type II–IV scale. Subjects were administered with either an oral dietary supplement containing 10 mg lutein (L) and 2 mg zeaxanthin isomers (Zi) (L/Zi: RR -zeaxanthin and RS ( meso )-zeaxanthin) or a placebo daily for 12 weeks. The minimal erythemal dose and skin lightening (L*) were measured via the Chromameter ® . The individual typological angle was calculated. Subjective assessments were also recorded. Results: Overall skin tone was significantly improved in the L/Zi group compared to placebo ( P <0.0237), and luminance (L*) values were significantly increased in the L/Zi group. Mean minimal erythemal dose was increased with L/Zi supplementation after 12 weeks of supplementation. L/Zi supplementation significantly increased the individual typological angle. Conclusion: L/Zi supplementation lightens and improves skin conditions. Keywords: lutein, zeaxanthin isomers, skin lightening, minimal erythemal dose, individual typological angle, overall skin tone