Tavakkol A, Nabi Z, Soliman N, Polefka TG.
Journal of cosmetic science ยท 2004
Read the original publication at PubMed
Abstract
Topical supplementation represents an attractive approach to mitigate environmentally induced deficiencies of skin vitamin E (alpha-tocopherol). We report here the impact of natural sunlight on stratum corneum (SC) vitamin E and also compare the effectiveness of dietary supplementation to topical application as a way to increase vitamin E in the superficial layers of the SC. The effects of natural sunlight, 30 minutes of midday sunlight, were measured on two separate occasions. Vitamin E in the surface layers of the SC was measured by HPLC after ethanol extraction. Under these relevant conditions, vitamin E in the superficial SC was reduced in a dose-dependent manner by 50-65%. In a followup study, panelists entered into a randomized, double-blind, vehicle-controlled study. In this study, one group washed their skin once daily for one minute with a commercially available body wash containing 0.15% vitamin E and 0.10% vitamin E acetate, while the second group used a body wash without vitamin E but also supplemented their diet with 400 IU alpha-tocopherol (18 x RDI). Not surprisingly, only dietary supplementation increased serum vitamin E (approximately twofold). Although both treatment modalities increased SC vitamin E, topical delivery was significantly more effective (53-fold vs baseline) than dietary delivery (eightfold vs baseline). Moreover, only topical delivery increased SC vitamin E acetate (19-fold vs baseline). The results reported here indicate that vitamin E in the superficial layers of the SC is depleted readily by even a brief exposure to sunlight and that use of a vitamin E body wash can substantially increase the vitamin E in this superficial layer more effectively than dietary supplementation.
