The polyphenol story
Green tea is rich in catechins - particularly epigallocatechin gallate (EGCG) - which behave as antioxidants when applied to skin and hair. The cosmetic literature on topical green-tea polyphenols is large and reasonably consistent: they reduce visible signs of UV damage, calm low-grade redness, and add a measurable barrier-support effect when included in moisturisers and serums. We use green tea at the concentrations the cosmetic-chemistry literature considers active, not as a marketing-only trace.
Why we put it in the hair line too
Green tea has also been studied as a scalp ingredient, where its astringent tannins help reduce sebum on oily scalps and its caffeine load gives a mild stimulant effect at the follicle. Our green-tea shampoo and hair oils combine those properties; the hair serum carries a higher concentration for people who want a leave-in. None of this is a hair-loss treatment - it is daily hair-care with a polyphenol bias.