EGCG From Green Tea Targets Cancer, Aging Skin, and Brain Health

Green tea has been consumed medicinally for millennia, but only recently has molecular science clarified why. This comprehensive 2025 narrative review, authored by dermatologists and clinicians from Sapienza University of Rome, Semmelweis University Budapest, and IRCCS San Raffaele Milan, synthesizes decades of in vitro, in vivo, and clinical data on epigallocatechin-gallate (EGCG), the predominant polyphenol in green tea (10–15% of dry leaf weight).

EGCG's potency derives from its distinct chemical architecture: a gallate ester at carbon-3 of the C-ring combined with trihydroxyl groups on the B-ring creates eight free hydroxyl groups capable of donating electrons to a wide spectrum of reactive oxygen species. This structure also enables EGCG to modulate signaling pathways including PI3K/Akt/mTOR, NF-κB, MAPK, and STAT3, explaining its broad biological reach. In vitro studies at concentrations of 5–200 µM demonstrate inhibition of proliferation, induction of apoptosis, and suppression of angiogenesis across 14 cancer types including breast, colorectal, prostate, lung, pancreatic, and skin cancers. The review notes that clinical translation remains cautious, with most human data still limited to pharmacokinetic and safety trials.

For dermatology—the review's primary clinical focus—evidence is particularly well-developed. Topical and oral EGCG has shown efficacy in reducing HPV-associated wart recurrence, dampening the Th17-driven inflammation of psoriasis, improving vaginal dryness and lichen sclerosus symptoms, suppressing sebum production and P. acnes in acne, and promoting hair follicle cycling in androgenetic alopecia. In aesthetic medicine, EGCG neutralizes UV-induced reactive oxygen species, inhibits matrix metalloproteinases that degrade collagen, suppresses tyrosinase to reduce hyperpigmentation, and modulates HIF-1α to limit pathological angiogenesis underlying rosacea.

Neurologically, EGCG crosses the blood–brain barrier and has been shown in animal models to reduce amyloid-β aggregation, tau hyperphosphorylation, and neuroinflammatory cytokines, pointing to potential in Alzheimer's and Parkinson's disease prevention. Cardiovascular data indicate EGCG reduces LDL oxidation, improves endothelial function, and lowers blood pressure via eNOS activation. Metabolic studies show inhibition of pancreatic lipase and amylase, improved insulin sensitivity, and modulation of adipogenesis-related transcription factors.

Bioavailability is a significant challenge. EGCG is optimally absorbed in a fasting, acidic gastric environment; food co-ingestion reduces Cmax and AUC substantially. It degrades rapidly above pH 4 and at temperatures above 80 °C, complicating incorporation into cosmetics and processed foods. Pharmacokinetic studies (Ullmann 2003; Chow 2005) show plasma concentrations above 1 µM require doses exceeding 1 g, and the European Food Safety Authority flags potential hepatotoxicity at daily intakes above 800 mg. Strategies to improve delivery include enteric-coated capsules, vitamin C or quercetin co-formulation, nanoencapsulation, and glucosylated EGCG-G1 for enhanced dermal penetration. The authors propose EGCG as a candidate daily foundational supplement, though they acknowledge the need for larger, well-controlled clinical trials to establish definitive dosing and safety guidelines.