Abstract
Carotenoids, classified into carotenes and xanthophylls, are natural lipophilic pigments that are widely distributed in plants. Red paprika is unique in its high levels of various xanthophylls. Dietary paprika xanthophylls have been shown to reduce UV-induced photo damage by the strong antioxidant activity in the skin. However, the precise effects of paprika xanthophylls on skin condition are still unknown. Here we show that skin moisture is enhanced by the intake of red paprika supplements including seven xanthophylls. We conducted a 4-week randomized, single-blind, parallel-group controlled trial to clarify the effects of dietary paprika xanthophylls on facial skin. The results showed that the moisture was significantly higher in the paprika intake group than in the control (21.0±8.9 vs 13.4±6.0 (A.U.)). There was no significant difference between the paprika and control groups in other parameters such as viscoelasticity, the number of wrinkles, and the amount of water evaporation. On the other hand, the number of brown stains in the paprika group increased significantly, to 190±26 from 173±30 (p < 0.05). In vitro experiments, quantitative real-time PCR showed that paprika extract led to increases in the gene expression of Aquaporin 3 (AQP3) and hyaluronic acid synthase 3 (HAS3) in cultured keratinocytes. Western blotting showed that the paprika extract enhanced AQP3 expression. Taken together, taking supplements containing paprika xanthophylls may provide beneficial effects of moisture on facial skin. The study provides new insights into understanding the role of paprika xanthophylls in the skin.