The t ea plant, Camellia sinensis , is most commonly known in three forms: (1) fully fermented black tea; (2) partially fermented oolong tea; and (3) unfermented green tea. Green tea's antioxidant properties are attributed to polyphenolic catechins, also known as flavan-3-ols. Catechins make up about 30–35% of the dry weight of the green tea leaf, and 90% of all polyphenols in green tea. Epigallocatechin-3-gallate (EGCG) is the most potent of the catechins and the active ingredient in green tea and GTE. Studies have demonstrated that topical GTE suppresses metalloproteinase and age-related Collagen cross-linking in mice. The optimal concentration, dosage, and route of administration must be determined and substantiated through future studies in order for GTE to reach its full potential as a botanical cosmeceutical.
Use
Green tea has thermogenic properties and promotes fat oxidation beyond that explained by its caffeine content per se. The green tea extract may play a role in the control of body composition via sympathetic activation of thermogenesis, fat oxidation, or both.