Green Tea
Green tea is a very popular beverage as well as an antioxidant, that is extracted from the plant Camellia sinensis. There are 4 major polyphenolic catechins, of which Epigallocatechin 3-gallate (EGCG) is the most abundant and biologically active. The green tea polyphenols (GTP) possess not only antioxidant activity, but they also act as anti-inflammatory and anticarcinogenic agents. GTP can be administered either orally or topically.[35] With various in vitro and in vivo studies, green tea is probably the most studied antioxidant. In vivo topical application of GTPs has been shown to suppress chemo- and photocarcinogenesis in mice,[36] and prevent UV-induced oxidative damage and induction of matrix metalloproteinases.[37] In human skin, GTPs reduced UV-induced erythema, the number of sunburn cells, immunosuppression, and DNA-damage.[38] In spite of the limited data in humans, there are numerous OTC products containing green tea, and using them every morning for photoprotection in combination with a sunscreen makes sense. As with most of the antioxidants, no controlled clinical trials exist and the concentration of phenols in the various products is not standardized.
Skin Therapy Letter. 2008;13(7):5-8. © 2008 SkinCareGuide.com
Cite this: Antioxidants Used in Skin Care Formulations - Medscape - Sep 01, 2008.
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