Camellia sinensis is a species of evergreen shrub or small tree whose leaves and leaf buds are used to produce tea. Green tea extract comes from the steaming and drying of the Camellia sinensis leaves. One of the most important components in green tea extract is the polyphenol epigallocatechin gallate (EGCG). This polyphenol has been extensively studied due to its potential health benefits.
When applied to the skin, the EGCG in green tea extract has been shown to provide significant preventive effects against photocarcinogenesis and phototoxicity in mouse studies. Furthermore, a 2001 study in the journal Carcinogenesis found that topical application of EGCG to human skin resulted in decreased oxidative stress and an increase in antioxidant enzymes after UV irradiation. Overall, green tea extract is an excellent ingredient to provide preventative anti-aging benefits in skin care products.