Effect of an Oral Formulation on Skin Lightening: Results from In Vitro Tyrosinase Inhibition to a Double-Blind Randomized Placebo-Controlled Clinical Study in Healthy Asian Participants

Abstract

Oral formulations with natural plant-based extracts represent a safe and promising strategy for skin lightening and anti-dark-spot effects, especially in Asia. This study evaluated the effect of an oral formulation including polyphenol-rich extracts and vitamin C (Belight3TM) on in vitro tyrosinase inhibitory activity and investigated its skin lightening and anti-dark-spot effects in vivo. Tyrosinase inhibitory activity of the formulation was measured with spectrophotometry. A randomized, double-blind, placebo-controlled clinical study was carried out on 58 healthy Asian males and females, aged 45–65. Skin color was measured at baseline, 6 weeks and 12 weeks with digital photographs. Color of dark spots was assessed with spectrophotometry. In vitro, the formulation showed a significant synergistic tyrosinase inhibitory activity of 85% compared to the control. In vivo, 12-week oral administration of the formulation significantly lightened the skin and was significantly better than the placebo. In addition, this formulation induced a slight and significant lightening effect of the dark spots after 6 and 12 weeks. Our findings suggest that the daily oral administration of Belight3TM during 12 weeks appears as an efficient and safe nutricosmetic to lighten the color of the facial skin and dark spots in Asian subjects.