The tea plant itself and its extracts together with their centuries-old tradition of use play an important role in the cosmetics market.
Green Tea is produced from the leaves, buds, or delicate stems of the plants of the genus Camellia. The most widely used plant species for tea is Camellia sinensis (L.) Kuntze.
Rich in caffeine and catechins.
TREATMENT OF WRINKLES AND DARK CIRCLES AROUND THE EYE
Green Tea improves eye contour appearance with emollient and anti-dark circle capacity.
Moisturizing Properties
Green Tea increases skin moisture, improves skin microrelief (skin texture), reduces skin roughness and enhances skin smoothness. It also improves the viscoelasticity of the skin.
Astringent Properties
Green Tea has astringent activity due to the presence of polyphenols and tannins. It interacts with the keratin present in the stratum corneum. This process also leads to a reduction in skin redness, irritation, and reduction of swelling.
Anti-inflammatory Properties
Green Tea soothes the itching and burning skin sensation. The latter effect results from the vasoconstriction induced by the metabolites of the tea plant and are shown up as a noticeable reduction of swelling around the eyes, which is often observed during inflammation.
Tea polyphenols have anti-inflammatory activity, which significantly improves skin microcirculation. This particular action is related to the radical scavenging properties of tea polyphenols, which decelerate the inflammatory processes, which disturb microcirculation, and protect the intracellular cement lipids. Moreover, inhibition of nitric oxides, prostaglandins, thromboxanes and leukotrienes, which are the main mediators of inflammation have been observed upon the administration of tea extracts.
Microcirculation improvement
Green Tea improves microcirculation and the condition of blood vessels, which results in better skin nutrition and oxygenation.
Caffeine is a crystalline compound that has vasoconstriction properties. It stimulates the blood circulation around the eyes and accelerates the flow of blood in the capillaries around the eyes.
Antioxidant Properties
Green tea extract, known to be an effective free radical scavenger, has antioxidant properties due to the presence of catechin and caffeine. The tea polyphenols exhibit significant protective effects against free radicals produced due to daily stressor, UV radiation, and the effect of the activity of the various enzyme.
It protects the cellular components and lipid from oxidation and destruction by neutralizing oxidative stress.
Caffeine is a powerful antioxidant that helps rejuvenate the skin and improve elasticity. It helps to neutralize the skin damaging free radical, which can cause a breakdown of collagen and cause wrinkles. In addition, it improves the crow’s feet wrinkles around the eye and periorbital wrinkles.
HAIR CONDITION IMPROVEMENT
Green Tea is recommended for patients with androgenetic alopecia and hair loss due to the presence of caffeine and catechins. It inhibits the activity of 5α-reductase, which results in a decreased DHT formation that causes androgenetic alopecia. It promotes hair growth in the dermal papillae of human scalps. It also stimulates hair roots and extends the hair growth phase (anagen phase).
Moreover, caffeine leads to a significant stimulation of human hair follicle growth. It reduces smooth muscle tension near the hair follicle and therefore significantly increases the delivery of nutrients through the microcirculation of the papillae of the hair.
TREAT ACNE VULGARIS
Green Tea reduces the inflammatory and non-inflammatory lesion counts and acne severity ( decrease papule and pustule count).
Antimicrobial: Green Tea has antimicrobial properties against Propionibacterium Acne, Propionibacterium granulosum, Staphylococcus aureus and Staphylococcus epidermidis which are bacteria present on the skin of acne patients. Additionally, catechin increased apoptosis of the SEB-1 cell line of sebocytes and led to a reduction in the mean colony forming units of P. acnes.
Decrease sebum production: Green Tea also modulates the M locus protein kinase-Sterol regulatory element-binding protein 1 (MLPK-SREBP-1) signaling pathway, which leads to a reduction in lipogenesis and sebum production.
Anti-inflammatory: Green Tea reduces transcription of the nuclear factor-κB (NF-ĸB) pathway and reduces inflammation.
Green tea is safe to be used in cosmetic products when formulated to be non-sensitizing.
https://online.personalcarecouncil.org/ctfa-static/online/lists/cir-pdfs/PRS658.pdf
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6930595/
https://pubmed.ncbi.nlm.nih.gov/23742288/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6412948/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6155403/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5384166/